"When you think about it, what you call people is how you treat people," he said.
The family's effort also caught the attention of Sen. Barbara Mikulski, D-Md., who introduced a measure called Rosa's Law in the U.S. Senate in November 2009.
"Rosa's Law is the perfect example of effective citizen advocacy," Mikulski said as she testified in the Senate. "A family that pulled together for their own. And in pulling together, they're pulling us all along to a new way of thinking."
In an e-mail to ABC News, administrators at Rosa's school, Central Elementary School in Edgewater, Md., said they "passionately supported the Marcellino legislative efforts at both the state and federal level. "
Nina Marcellino said she didn't think the new law would end the use of the word. "We call it the playground use of the word," she said. "I think this legislation has brought everything to the forefront and everybody's talking about it now."
"The most important thing about Rosa's Law is respect," Paul Marcellino said. "For all her peers, all her friends. Everybody who she's around. They won't be using that word to describe my daughter anymore. That's the main thing."
ABC News' Susan Donaldson James contributed to this story.