Juan Sotomayor on Sister Sonia's Critics: 'Angry Is Just the Beginning'

Dr. Juan Sotomayor, brother of Supreme Court-nominated judge Sonia Sotomayor, broke his silence about his sister's critics, saying the "insulting" comments about her do not describe the woman he grew up with.

"Anyone who knows my sister, she has so many people who love her, adore her; so many people she's friends with; so many people that respect her," he told "Good Morning America" in an exclusive interview. "It's just insulting."

ABC News' senior national correspondent Claire Shipman sat down for an exclusive interview with Sotomayor, who is the nominee's only sibling. He talked about his relationship with his older sister, his pride in her achievement and his reaction to recent criticism of the nomination.

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"Angry is just beginning of the emotion that I could describe," he said.

In the emotional interview, Sotomayor also expressed overwhelming pride in his big sister.

He cannot even look at the display dedicated to his sister at their former high school without tearing up, but said he is "not surprised" that she has risen to the national stage.

"You just don't understand how a brother can feel," said Sotomayor, a physician practicing in Syracuse, N.Y. "It's, you know, you live with someone your whole life and you know it's just great."

Outside the harsh spotlight of American politics and relentless media attention -- in which Sonia Sotomayor, 54, has been characterized as everything from an "excellent choice" to an "interesting" one, to a "racist" -- her brother paints a more personal portrait of a sister who grew up strong-willed, focused on the family and was "the life of the party."

"You grow up with someone and you know what kind of person ... there's no mystery with my sister," he said. "She's a wonderful, warm person, one of the greatest family people you'll ever meet. [She] takes being a family member very seriously, just like she takes everything else."

Sonia Sotomayor's Brother: 'I'm Really Proud of Her'

Sonia and Juan Sotomayor's father died when they were children, at which point their mother raised them alone in a New York City public housing development.

Juan Sotomayor says he now sees his sister four or five times a year, but that they "both have very busy lives." If Sonia Sotomayor is confirmed as a Supreme Court justice, her life would only get busier. But Juan Sotomayor is not perturbed.

"For me and her, we have a relationship born out of the ... there was just three of us, really. It was a core group and that was our family," he said.

And although he said he was an "irritating" little brother, Juan Sotomayor said his sister took care of him. Now that she's at the doorsteps of the highest court in the land, a familial pride is unmistakable.

"[I'm] just really proud of her," he said. "No other word to say it. No other words to describe how you feel. It's just a great feeling.

"Now, I know how my mom feels."

Watch the full interview on "Good Morning America" Wednesday at 7 a.m.