I don't think children are any more resilent than anyone else. They're just people with little bodies.
“If I fell down and hurt myself, I never cried. There was no one to hear me.”
“And then finally, I'm the commander, so I am fundamentally responsible for the lives of the other people on board and the health and longevity of the space station. I need to bring six people back happy, healthy and feeling like they've had the best six months of their life.”