Her father Francis said he always knew his math-oriented daughter was a glamour girl. She and her sisters used to strut around and pretend they were beauty queens.
"They would model around the pool," he said.
Her sister Audrey, 20, said with tears in her eyes that her grandmother would orchestrate the shows.
"She'd be like, 'prance around the pool like Miss America.'"
The family was taken by surprise when Brady announced that she would be entering the Miss Connecticut competition two years ago, but cheered her on.
"She just went up there on a whim, man. But it was like, 'Just go for it. There should be more people like you who are competing, where it's not all about the hair and the makeup, but personality too,'" Audrey said.
Fiancee Tony Capasso said it was her winning personality that propelled her to the crown. He said he advised her to compete without makeup.
Brady told The Associated Press she hopes that her background will help dispel the image held by some of the bimbo beauty queen.
"I think that now more than ever, they're accepting that we're all intelligent individuals and that it's really not a stereotype anymore," she said.
Unlike the rival Miss America pageant, Miss USA doesn't ask its queens to perform a talent or choose a charity mission.
Brady will represent the United States at the Miss Universe pageant in Moscow this winter.
Last year's Miss USA, Olivia Culpo, won that international crown, becoming the first Miss USA to ascend to Miss Universe in 16 years.
Brady said she is determined to pull of that feat for the U.S. again.
In the moments before she won, Brady held hands with first runner up Mary Margaret McCord, of Alabama. McCord could be seen saying, "I love you" in the moments before the winner was announced. Miss Illinois Stacie Juris was second runner up.