California teen who cared for abused siblings now battling cancer

ORANGE, Calif. -- A California couple hopes to raise the spirits of their 19-year-old foster child Joshua by asking people to send messages of encouragement.

We family first made headlines in 2016, when Joshua and his two younger brothers and sister moved in with their foster parents, Mark Sanchez and his fiancee Valerie.

We're not using Joshua's last name or identifying his siblings because the younger children are victims of what prosecutors call a "heartbreaking case" of alleged child sex abuse dating back to 2014.

The children ranged in age from 6 to 12 at the time.

An investigation began after Joshua's siblings told Sanchez about the alleged sexual abuse. Brandi Valadez, 40-years-old at the time, was arrested.

She pleaded not guilty and remains in jail awaiting her next court hearing. Prosecutors are not saying how Valadez knew the children in order to protect their identities.

Joshua, who often was left to feed and care for his siblings when he was just 14, said he was living elsewhere at the time of the alleged abuse and only learned about the allegations through Sanchez.

"I felt really bad for them," said Joshua. "I wasn't there to help them."

Since moving in with Sanchez's family, the kids have undergone therapy. They've also shared their first real holidays together.

Joshua enrolled in college, studying to become a respiratory therapist.

"The family was getting closer and things started to get better and then we kind of got side-tracked," Sanchez said.

Last October, Joshua was diagnosed with testicular cancer. It spread to his lungs and liver.

He's undergone radiation at CHOC and lost 100 pounds. He said he's had so many doctor's visits, he's lost count.

"Life happens," Sanchez said. "We do our best with what we have, but it's just a lot."

The couple already had six children of their own, including a son with special needs.

Sanchez is a graphic designer. Valerie is a stay-at-home mom.

A vehicle with mechanical problems makes getting to hospital appointments a challenge. Still, Joshua doesn't complain.

"All I can do is try my best to do good, to be positive. Don't let anything negative get to me."

"Joshua is an inspiration," said Sanchez. "He's got a lot of strength, this kid."

Sanchez is asking people to send messages with positive words, as Joshua prepares to undergo stem cell treatment and more chemotherapy in the coming weeks.

"You would be surprised what a few words can do to somebody's spirit," Sanchez said. "It really can change their day."

If you'd like to send a message to Joshua, share on social media using #abc7eyewitness and we'll pass it along to him.

If you would like to send something, you may send it to ABC7 OC Bureau address: c/o Reporter Eileen Frere, 770 The City Dr, S., Suite 6000, Orange, CA, 92868.

Sanchez has also set up a GoFundMe page.