The leggy Brazilian is already mum to Benjamin, two, her son with husband, Tom Brady, and step mum to Tom's four-year-old son, Jack.
The Boston Herald claims Gisele and Tom have announced the news to close family and friends. It also says the supermodel told her dress designer that she was two months into pregnancy so he could alter a frock for her growing tum.
Tom then fuelled the rumours by posing on the red carpet at the Met Ball with a protective hand over his wife's belly (which of course at the moment is non-existent).
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