Our Pediatricians

At Lone Tree Pediatrics, we are dedicated to helping you and your child feel at home from the moment you walk through the door. We pride ourselves in being an exceptional pediatric practice where your children come first. Our pediatricians and medical staff are highly trained professionals and maintain the highest level of accreditation in pediatrics to address the special needs of infants, children, and teens.

Matthew Hadeed is no longer practicing primary care.

dr debra berry md pediatrician Debra M. Berry, M.D.

Dr. Debra Berry is a warm, compassionate board-certified pediatrician treating patients in Lone Tree, Colorado, and the surrounding communities. Her primary goal as a physician is to help each of her patients live a healthy life and grow into a happy productive adult. She treasures being a part of every stage of a child’s life — from the early days of a newborn’s life through childhood and into the formative teenage years.


Dr. Berry graduated Phi Beta Kappa from the University of North Carolina at Chapel Hill. She attended the University of Tennessee College of Medicine on a full academic scholarship as part of the Gooch Scholar program. At UT, she also received the Dorothy Snider Award and was named the Outstanding Medical Student in Pediatrics. Dr. Berry completed her internship program and residency training at the University of Colorado here in Denver. She holds certification from the American Board of Pediatrics, was named to the Alpha Omega Alpha Medical Honor Society and is a member of the American Academy of Pediatrics.


Dr. Berry has been named Best of the Best of Pediatricians in Lone Tree and currently serves as the chair of pediatrics at Sky Ridge Medical Center. When she is not treating patients, Dr. Berry enjoys trail running, mountain biking, hiking, reading, and spending time with her husband, son, and daughter.

dr emily vangeti md pediatrician Emily Vangeti, M.D.

Dr. Emily Vangeti grew up in the Monument area and graduated from Lewis Palmer High School. As a physician, she strives to connect with each of her patients and their families. She cherishes playing a role in lives of children of all ages. Dr. Vangeti is a board-certified pediatrician.


Dr. Vangeti graduated from the University of California – Santa Barbara and was also a member of Phi Beta Kappa. She received her Bachelor of Science in Biological Science and then went on to earn a Master’s of Science in Physiology at Georgetown University. She attended medical school at Jefferson Medical College in Philadelphia. While there, she received the Edward J. Moore Award for Aptitude in Pediatrics. She completed her residency in Delaware at A.I. DuPont Hospital for Children. She holds a certification from the American Board of Pediatrics.


Dr. Vangeti met her husband in medical school, and they were overjoyed to welcome their daughters, Neela, in 2014 and Ella, in 2017.  As a newer mom, Dr. Vangeti understands the concerns and worries that come with being a parent. When Dr. Vangeti is not practicing pediatrics, she enjoys spending time with her family, along with reading, traveling, exercising and cooking.

dr david roos md pediatrician David Roos, M.D.

Dr. David Roos is a board-certified pediatrician, and has been a practicing pediatrician since 1982. With over thirty years of experience, Dr. Roos provides the best caliber of care to his patients. He places a great deal of emphasis on the physical and emotional well-being of each of his patients.


Dr. Roos received his degree from the University of Colorado Medical School. He completed his Internship and Residency in the Denver area as well. His particular pediatric interests include: diabetes, care of the premature infant, and the treatment of behavioral and emotional issues, including ADD/ADHD. Dr. Roos was the Chief of the Pediatrics Department at the Medical Center of Aurora South. In addition, he served on the board of Colorado Pregnancy Centers in Aurora, CO as the Vice President, and was a board member of the Inner City Health Center in Denver, CO. He holds a certification with the American Board of Pediatrics. His other memberships include: American College of Pediatricians, Colorado Medical Society, American Association of Pro-Life Pediatricians, and served as President of the Colorado Chapter of the Christian Medical/Dental Society.


When Dr. Roos isn’t at the practice, you’ll find him with his wife, Janie, and their four children and six grandchildren. In addition to quality family time, Dr. Roos plays guitar, gardens, skis, and enjoys traveling.

dr lisa haynes md pediatrician Lisa Haynes, M.D.

Dr. Haynes is a board-certified pediatrician who comes to us with 18 years of experience in pediatrics. She graduated from the University of Arkansas College of Medicine at Little Rock, where she also completed her residency in 2002. She then went on staff at the Arkansas Children’s hospital where she continued to develop her passion for pediatric medicine. Dr. Haynes specializes in adolescent medicine and has three years of experience working in a pediatric ER. In addition to this, she also has significant experience with neurology as she spent a year in a neurology clinic. Lisa has been in private practice since 2012 and is affiliated with Children’s Hospital Colorado, Littleton Adventist Hospital, Skyridge Medical Center and Swedish Medical Center.

When not in the office she enjoys teaching about pediatrics and spending time with her three children.

Nancy Taoka, M.D. Nancy Taoka, M.D.

Dr. Nancy Taoka has been a pediatrician in the Littleton area for almost 20 years and has just joined Lone Tree Pediatrics. She grew up I Kansas and attended the University of Kansas Medical School (and is a huge Jayhawk basketball fan!). She came out to Denver for Pediatrics Residency at the University of Colorado and now can’t imagine living anyplace but Colorado. She enjoys traveling, however, and expresses her artistic side through scrapbooks of her travels. Her scrapbooks also show her skiing, serving the community with her Rotary Club, or cheering at a Rockies baseball game.


Anju Kannappan, DO Anju Kannappan, DO

Dr. Kannappan received her undergraduate degree in Biology from Baylor University in Waco, TX, her medical degree from the Texas College of Osteopathic Medicine in Fort Worth, TX, and completed her pediatrics residency at the University of Oklahoma Health Sciences Center in Oklahoma City. She is passionate about all things pediatrics, but has a special place in her heart for adolescent medicine. Specifically, she has interests in mental health, reproductive health, and LGBTQ+ care. She takes great honor in serving as an advocate for her patients and their families and cherishes the connections she is able to make with them. Though a Texas native, she is excited to relocate to Denver to be closer to family and take full advantage of all the beautiful hikes Colorado has to offer!

Dr. James Boone, DO James Boone, DO


Dr. James Boone is an enthusiastic pediatrician who strives to make a positive impact on the lives of his pediatric patients. He grew up in Alexander City, Alabama and graduated with a Bachelor of Science degree in Business Management from the University of Alabama. Roll Tide! He attended Edward Via College of Osteopathic Medicine and completed his didactic years in Auburn, Alabama and clinical training in Roanoke, Virginia. After medical school, DrBoone completed his pediatric residency at Good Samaritan Hospital in West Islip, New York. DrBoone and his wife are very excited to be starting the next chapter of their lives in Colorado. In his spare time, DrBoone enjoys trail running, hiking, fishing, and spending time with his wife and golden retriever, Lady Bug.


• American Osteopathic Association
• American College of Osteopathic Pediatricians
• American Academy of Pediatrics

Favorite Tip for Good Health:
“You only get one body, so take care of it. Set attainable goals and create healthy habits early. The earlier you create a healthy lifestyle, the easier it will be to maintain.”

Hannah Salter, PNP Hannah Salter, NP

Hannah Salter is a friendly and compassionate board-certified Pediatric Nurse Practitioner originally from Seattle, WA. Hannah completed her Bachelor of Science degree in Neuroscience at The University of Southern California. After graduating college, Hannah obtained a BSN in Nursing at Johns Hopkins University, in Baltimore, MD. Hannah worked for several years in the Neonatal Intensive Care Unit at Children’s National Medical Center in Washington, DC as a bedside nurse. Meanwhile, she obtained her Pediatric Nurse Practitioner degree at Johns Hopkins University where she graduated with honors. Before relocating to the Denver area, Hannah worked as a Pediatric Nurse Practitioner for several years at Pediatric Associates of Alexandria, a large private practice in Alexandria, VA. Hannah is a member of the National Association of Pediatric Nurse Practitioners.


Hannah has clinical interests in care of the premature infant, asthma management, and breastfeeding support. When Hannah’s not in clinic, you’ll find her hiking with her dog, cooking, reading, and exploring national parks.

Lindsey Haight, CPNP-PC Lindsey Haight, CPNP-PC

Lindsey grew up wanting to work in pediatric medicine and attributes that to having a great pediatrician herself. “I love kids and I’m extremely passionate about educating and empowering my patients and their families to live their healthiest and happiest lives!”

Lindsey Haight is experienced in pediatric primary care working with patients of all ages. She is a member of the National Association of Pediatric Nurse Practitioners & The Colorado Society of Advanced Practice Nurses

“I am particularly passionate about newborn medicine and breastfeeding support. I have additional interests in asthma management as well as childhood obesity. There is a meaningful benefit for almost everyone to get some sort of physical activity! That can mean taking a 30-minute walk outside with their family or can include playing in the backyard with friends or siblings. The benefits are endless not only for our physical health but for our mental health as well!”

Lindsey is a Colorado native and loves being able to practice medicine and provide care to patients in the same area that she grew up. When not working, you can usually find Lindsey spending time with her husband, daughter and Bernese Mountain Dog, Baloo! “I love being outside – hiking, running, paddle boarding, camping, etc. When I’m not outside, I’m most likely in the kitchen baking something sweet for my family!”

Jordan Zielinski, NP Jordan Zielinski, NP

Jordan is a board-certified Pediatric Nurse Practitioner originally from Atlanta, GA. She absolutely loves working in pediatrics and helping families to create and maintain healthy lifestyles. Jordan attended the University of Georgia College of Public Health to earn a Bachelor of Science in Health Promotion and Behavior. This is where she developed her love of primary care and knew she wanted to pursue a career to keep kids healthy and out of the hospital! Jordan continued her education at Emory University in Atlanta to earn a Bachelor of Science in Nursing and a Master of Science in Nursing. She always knew she wanted to specialize in pediatrics, as she loves how kids and teens are resilient, curious, and fun to work with! Jordan is a member of the National Association of Pediatric Nurse Practitioners and was inducted into the Sigma Theta Tau International Honor Society.

When Jordan is out of the office, you will find her spending time with friends and family, traveling, long-distance running, watching sports (Go Dawgs and Go Braves!), or spending time outside! She could not be more excited to be part of the Lone Tree Pediatrics family and cherishes every moment she gets to spend with her patients and their families!

Jordan Lange, M.D.

Dr. Jordan Lange, MD is excited to join the Lone Tree Pediatrics team! He is passionate about his patients, forming long-lasting relationships with his families, and above all, providing excellent patient-centered care. A child’s care is a group effort, and the physician is no more important than the family members or the child themselves. He loves working collaboratively with his patients and families to provide the best care possible. He believes in being a life-long learner and knows that our learning doesn’t end once our degrees are achieved, but it’s only the beginning!

Dr. Lange received his undergraduate degree at University of Illinois at Urbana-Champaign in Molecular and Cellular Biology. He then graduated from Southern Illinois University in 2017 with a Doctorate of Medicine. He went on to complete his pediatric residency at Advocate Christ Children’s Hospital near Chicago, IL. In 2020, he moved out to Colorado with his wife and family, and has been in private practice in Lakewood until 2023.

Jordan enjoys spending time with his wife and three wonderful children. He is an avid sports fan and loves watching his favorite team, the Illinois Fighting Illini (for better or for worse). He enjoys hobby board games, playing music and singing, and exploring what CO has to offer!