Twins unleashed

Formerly conjoined, the girls are flourishing

Kevin Fiscus photograph of formerly conjoined twins Eva, left, and Erika Sandoval.

Formerly conjoined twins Erika and Eva Sandoval are lively 5-year-olds with a lot to say. I experienced this firsthand when I spoke recently with them and their mom, Aida Sandoval. She put me on speaker phone, and I asked the girls what they like about kindergarten, which they attend near their family’s home in Redding, California.

“I like going on the slide!” Eva shouted.

“I like choice time!” Erika responded, matching Eva’s zeal.

“I like choice time, too!” Eva yelled.

The twins’ enthusiasm for exploring the joys of kindergarten is just one indicator of how far the girls have come since they were born at Lucile Packard Children’s Hospital Stanford in 2014 and their anatomy resembled two people above the rib cage, merging almost to one below the bellybutton.

The twins were separated in a 17-hour, 50-person procedure performed at the hospital in December 2016 that required months of planning. There was no guarantee that both girls would survive surgery and recovery.

If they did, each twin would have one functional leg and would lack many abdominal muscles; at first, their surgeon wasn’t sure they’d be able to sit without support. Everything from how much blood the twins might lose to how they’d handle the emotional impact of being separated had to be figured out one step at a time.

Sandoval and her husband, Art, decided the risks were worth it.

“We know that this is the right path for them: to be independent, have the chance to succeed and explore, on their own, everything the world has to offer,” Aida Sandoval said when the surgery was finally complete.

Today, Erika and Eva are into typical 5-year-old stuff, Sandoval told me: They are learning numbers and love playing with kinetic sand, finger puppets and Barbie cars. The girls have also started bringing big words home from school. After a lesson about bees, they came back chattering about bee anatomy, popping out terms like “abdomen” and “thorax.”

“I’m in awe at the conversations they have with me sometimes,” she said.

They’ve made tremendous progress in their physical recovery and mobility, from sitting unassisted in early 2017, to using wheelchairs later that year, to being fitted in 2018 with custom leg prostheses.

The dynamic between them has also changed. Before separation, Eva was larger and dominated the twins’ relationship. In the months after surgery, Erika’s growth caught up to her sister’s, and play therapy at Packard Children’s helped them understand that it was OK to be separated. They have a strong sibling bond but also distinct personalities, likes and dislikes.

Both girls are getting around with a combination of prosthetic legs and walkers. The long-term goal is for them to use their prostheses with walking sticks for balance and support.

“Erika loves to get her prosthetic on and walk with us around the house,” Sandoval said. “I can picture how she’ll be doing it on her own as she gets older.” It’s a very positive change from the girls’ infancy, when their parents worried that they might not be able to have independent lives.

Eva and Erika enjoy seeing photos of themselves from when they were tiny and love to hear what life was like before they were separated.

“When I see the pictures, I can’t believe we were there,” Sandoval said. “It still amazes me to see them at this point in their lives.” 

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Erin Digitale

Erin Digitale is the pediatrics senior science writer in the Office of Communications. Email her at

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