WE were onto something with our Gisele Bundchen sighting last month. People magazine reports that pals of the Brazilian bombshell are saying she’s indeed pregnant by her husband, New England Patriots quarterback Tom Brady. Pregnancy rumors have been swirling around the catwalk queen since early in May, when we first sighted Bundchen walking out of a Park Avenue OB-GYN medical office with her pigskin-playing spouse. Her reps have refused to say if the supermodel really is expecting, although she was spotted with a noticeable babylike bump during a fashion show in Brazil on Wednesday. But yesterday, a source told People that she’s “ecstatic” and is due early next year. The child will be the second for Brady, who already has a kid with his former girlfriend, actress Bridget Moynahan.