America — and Hollywood — is saddened and outraged by the Feb. 26 death of 17-year-old Trayvon Martin, who was shot and killed in his gated community in Sanford, Fla. Wearing a hoodie and coming back with candy and an iced tea from a local 7-11, young Trayvon was unarmed, but George Zimmerman, a volunteer watchman patrolling the neighborhood, opened fire.

Zimmerman, 28, claimed that he shot Trayvon in self-defense, but a 911 call between Zimmerman and a dispatcher suggests there was no confrontation. Zimmerman (who told the dispatcher Martin looked "suspicious") has yet to be charged with any crime; he cites Florida's Stand Your Ground law, which permits Florida residents to use lethal force if they believe that their life is in danger.

As Travyon's grieving parents — father Tracy Martin and mother Sybrina Fulton — lead a movement to bring Zimmerman to justice, they have a huge swell of support from celebrities and leaders alike.

"If I had a son, he'd look like Trayvon," President Barack Obama said at the White House Friday.

"Obviously, this is a tragedy," Obama said. "I can only imagine what these parents are going through, and when I think about this, I think about my own kids, and I think every parent in America should be able to understand why it is absolutely imperative that we investigate every aspect of this and everybody pulls together – federal, state and local – to figure out exactly how this tragedy happened."

Director Spike Lee took to Twitter to quote Obama's moving words. Roseanne Barr tweeted to Sybrina Fulton, who is now on Twitter herself, "we will fight w u 4 justice & decency! All of my sympathy goes to u and yours-Trayvon is america's son."

Will Ferrell wrote angrily, "I live n a country where a chick that threw flour on Kim Kardashian was arrested on site But the man who KILLED Trayvon Martin is still free."

Said Vivica Fox: "Wanted to send out my support to Trayvon's family! May your son rest in peace and I promise u we wont 4get him! No justice! No peace!"

"Justice for #TrayvonMartin…sign the petition for Geo Zimmerman's arrest. God forbid if this happened to your child," said Sherri Shepherd.

Other stars lending their support included Kim Zolciak, La La, Common, Diddy, Taraji Henson, Kimora Lee Simmons, Joel Madden and others.