Mollie Tibbetts' mother asks for donations for Mollie's birthday

DES MOINES, Iowa (CNN) - The mother of an Iowa student who was brutally killed last year is making an emotional appeal on her daughter's birthday.

Mollie Tibbetts would have turned 21 on Wednesday. May 8, and her mom is asking everyone to donate $21 to "Mollie's Movement."

"Mollie's Movement" is a fundraiser for an adolescent psychiatric unit at the University of Iowa Children's Hospital.

"There's a picture that was done, a 'Mollie's Movement' picture, which I have framed and put in the psychiatric unit at the U of I, and I have people I know whose children are being treated there who said, 'Oh, I was there and I saw it,' and 'How wonderful,' so people are recognizing it," Laura Calderwood, Tibbetts' mother, said.

Calderwood says donations could help prevent tragedies like her daughter's from happening to others.

She says the suspected killer, Cristhian Bahena Rivera, suffered from mental illness, and if someone helped him when he was a child, her family's heartbreak might have been prevented.