Johnny Galecki is a Belgian-born American actor, best known for his roles as David Healy in Roseanne, Rusty Griswold in National Lampoon's Christmas Vacation, and as Leonard Hofstadter in The Big Bang Theory.
Groot was born on a distant and unknown planet, and after being captured by alien scientists, he meets Rocket there in the laboratory and escapes from that prison. Now they flee to land and stay there to spend in New York
