About Us


Steve Mousser, MD

Dr. Mousser began in office practice in 2000 in the East Valley. Then in 2002, along with Dr. Banerjee, formed Desert Pediatric Hospitalists, which later grew to one of the largest pediatric hospitalist practices in the state.

In 2005 he, with Dr. Banerjee and Dr. Zeidler, co-founded Cornerstone Pediatric Urgent care (now AllKids Urgent Care), one of the first child-only urgent cares. He continues to be associated with AKUC, but does not see patients there.

With a desire to return to office primary care, where he can care for his own patients, Dr. Mousser started All-Star Pediatrics - opening in November 2011.

He looks forward to the opportunity to see and care for your children.


Steven Milius, DO

Dr. Milius was born and raised in Mesa.  He did live in Chicago for four years for medical school, but he wanted to return home to the East Valley with his family.  Fortunately he was able to come home and completed his residency at St. Joseph's Hospital in Phoenix.  During that time, Dr. Milius worked at Cornerstone Pediatric Urgent Care where he became acquainted with Dr. Mousser.

After residency, Dr. Milius worked with Dr. Mousser with Desert Pediatric Hospitalists.  He continued to be a hospitalist, taking care of newborns and sick children in the hospital, until he joined Dr. Mousser at All-Star Pediatrics in September 2012.  Dr. Milius has always wanted to care for the children where he grew up, and now he can.

He looks forward to taking care of your children and watching them grow.


Ryan McClellan, MD

Dr. McClellan grew up in a military family and has lived in multiple places across the US and abroad. Arizona was always a home away from home so he is excited to be able to practice medicine in Arizona. He also spent almost 2 years abroad in Spain as a missionary for his church and is fluent in Spanish.

After completing medical school in West Texas, Dr. McClellan came to Phoenix Children’s Hospital and Maricopa Medical Center where he completed residency.

He is excited to join All-Star Pediatrics and get to know our wonderful staff, patients and families.


Kathy Waldo, CPNP

Kathy was born and raised in the Valley with an early calling to work with children and pursue medicine.  She started her nursing career at The Children’s Hospital in Denver, CO followed by now Cardon’s Children’s Hospital in Mesa, AZ after moving back home to AZ.  Since obtaining her graduate degree in 2008, Kathy is thrilled to have been providing primary pediatric medical care in the East Valley where she lives with her husband and three young boys.

Kathy is particularly passionate about serving her young patients and their caregivers with compassion and feels it is a great privilege to share in their health and growth.  She is excited to work with the skilled All-Star Pediatrics team and greatly looks forward to meeting all of you!