PALO ALTO, Calif. (KGO) -- A teenager from Danville is using "the force" for good.
On Saturday, Ryan Tam, who is a leukemia survivor, dressed up with his family as Star Wars characters and head to the Lucille Packard Children's Hospital at Stanford.
Ryan, dressed as the storm trooper, survived a cord-blood transplant at the hospital at just a year old.
He's now been cancer free for 13 years.
His goal every year for the past 12 years is to bring hope to other kids battling cancer.
Danville teenager entertains children with cancer