Britney Spears to have twins?

"Britney is only supposed to be five months along," says a source, "but she already looks like she's gained nearly all the weight she is supposed to have throughout her pregnancy."

"Lately, they've been reluctant to talk about whether Brit might be expecting a boy or a girl," says the source. "Instead, they cryptically give the answer that she's expecting a boy one week, and a girl the next."

Another clue is that Britney's been seen shopping for both girls and boys clothes. "Kevin [who's already got two kids with Shar Jackson] would probably freak over double duty," another source laughs, "but Britney would be over the moon!"