Meet Our Pediatric Providers

Our doctors and nurse practitioners specialize in caring for children.

Our Doctors

Paulina Avendano, MD

Paulina Avendano, MD, FAAP

Dr. Avendano has been with SOCPA since 2007. She is currently providing care Tuesday and Friday in our San Clemente office located in the community of Talega.

Eric Ball, MD

Eric Ball, MD, FAAP

Dr. Ball has been with SOCPA since 2006. He is currently providing care Monday, Wednesday, Thursday and Friday in our Ladera Ranch office.

Regina Brown, MD

Regina Brown, MD, FAAP

Dr. Brown has been with SOCPA since 1989.  She is currently providing care Tuesday, Wednesday, Thursday and Friday in our Lake Forest office

Terrence Cbu, MD

Terence Chu, MD, FAAP

Dr. Chu has been with SOCPA since 2001.  He is currently providing care Monday through Friday in our Lake Forest office.

Cynthia Dimalanta, MD, FAAP

Cynthia Dimalanta, MD, FAAP

Dr. Dimalanta has been with SOCPA since 2014. She is currently providing care on Tuesdays and Thursdays in our Rancho Santa Margarita office.

Lauren Dwinell, MD, FAAP

Lauren Dwinell, MD, FAAP

Dr. Dwinell has been with SOCPA since 2003. She is currently providing care Monday through Friday in our San Clemente office located in the community of Talega.

Kenson Lo, MD, MPH, FAAP

Kenson Lo, MD, MPH, FAAP

Dr. Lo has been with SOCPA since 2013. He is currently providing care Monday, Tuesday, Thursday and Friday in our Ladera Ranch, Rancho Santa Margarita and Talega offices.

John Mersch, MD

John Mersch, III, MD, FAAP

Dr. Mersch has been with SOCPA since 1982. He is currently providing care Monday, Tuesday, Wednesday and Thursday in our Ladera Ranch office.

Stephen Tang, MD

Stephen Tang, MD, FAAP

Dr. Tang has been with SOCPA since 2001. He is currently providing care Monday, Tuesday, Wednesday and Thursday in our Rancho Santa Margarita office.

Margaret van Blerk, MD, MPH, FAAP

Margaret van Blerk, MD, MPH, FAAP

Dr. van Blerk has been with SOCPA since 2008. She is currently providing care Monday and Wednesday in our San Clemente office located in the community of Talega.

Jenna Timboe, MD

Jenna Timboe, MD

Dr. Timboe has been with SOCPA since 2017. She is currently providing care Monday, Tuesday and Wednesday in our San Clemente office located in the community of Talega.

Katherine Williamson, MD, FAAP

Katherine Williamson, MD, FAAP

Dr. Roberts has been with SOCPA since 2012. She is currently providing care Monday, Tuesday, Wednesday and Friday in our Ladera Ranch office.

Rose Zaragoza, MD

Rosette Yson-Zaragoza, MD, FAAP

Dr. Yson-Zaragoza has been with SOCPA since 2005. She is currently providing care Monday through Friday in our Rancho Santa Margarita office.

Our Nurse Practitioners

Pediatric Nurse Practitioners (PNPs) are very special healthcare providers who are dedicated to improving children’s health. PNPs have advanced education in pediatric nursing and healthcare and they serve children and families in an extensive range of practice settings. Working with pediatricians and other healthcare providers, PNPs have been enhancing the healthcare of children for over 30 years.

Judi Leonard, MSN, CPNP

Judi Leonard, MSN, CPNP

Judi Leonard has been with SOCPA since 2008. She is currently providing care Monday, Wednesday, Thursday and Friday in the Lake Forest office.

Melody Mitchel, MSN, CPNP, CNS

Melody Mitchel, MSN, CPNP, CNS

Melody Mitchel has been with SOCPA since 1997. She is currently providing care Monday, Tuesday, Thursday and Friday in the Ladera Ranch and Lake Forest offices.

Anneke Sager, MSN, CPNP

Anneke Sager, MSN, CPNP

Anneke Sager has been with SOCPA since 1999. She is currently providing care Monday, Tuesday, Wednesday and Thursday in all SOCPA offices.

Lisa Walpert, MSN, FNP

Lisa Walpert, MSN, FNP

Lisa Walpert has been with SOCPA since 1999. She is currently working Tuesday, Wednesday and Friday in the Rancho Santa Margarita office.

PNPs serve as pediatric healthcare providers for sick and well children of all ages. PNPs offer a variety of services including:

  • Provide health maintenance care for children, including well exams
  • Perform routine developmental screenings
  • Diagnose and treat common childhood illnesses
  • Provide anticipatory guidance regarding common child health concerns
  • Perform school physicals

Many parents choose a PNP as their child’s provider knowing they will receive individualized quality healthcare!

If I could give 7 stars, I would! Every doctor is wonderful, Lisa, the nurse practitioner is fantastic as well as the girls up front! Both our kids have gone here since birth and we are beyond pleased! My kids had some complex medical issues and had been misdiagnosed. The doctors here diagnosed correctly and after short treatment and food changes, we have very healthy kids!

Danielle V., Anaheim, CA

Love taking my son to Dr. CHU. He has seen my son since he was born, I can’t say enough good things about him. He is really smart, he listens to everything and anything you want to address and he is very thorough. I would also like to mention all of the nurses and nurse practitioners are really good. The facility is always very clean. Another thing- they have really helped me squeeze my son in for an emergency appointment….5 stars!!!

Lydia M., Irvine, CA

Both of my children go here and I couldn’t be happier with them! From the great office staff that makes every visit simple and fast to the incredible nurses that always make my children ages 5 months and 4 yrs feel like family,

Marcus G., Anaheim, CA