"He's a beautiful, healthy boy," says the new mom's twin sister, Patricia, who was in Boston along with Bündchen's mother Vania at the time of the birth. "We are all really happy!"
And those relatives who weren't able to make the trek to Boston from the 29-year-old supermodel's hometown of Horizontina, Brazil, are eagerly awaiting every detail.
"We don't know the name yet. I don't have all the details. But obviously when someone is born into the family, it makes us all happy," Bündchen's father, Valdir, tells PEOPLE. "We are all here in Horizontina, and my wife is there in Boston, so obviously we are a little distant, but we are all immensely happy."
Only one thing could make it better: a visit from his daughter and husband Tom Brady – pronto!
"Obviously I have a huge desire to see my grandson," he says. "The arrival of a grandson always brings happiness to the grandfather."