Gisele Bundchen says discovering Tom Brady had a love child was a "wake up call".

The Brazilian supermodel, who married American football star Brady in February, was left reeling after Tom's ex-girlfriend, Bridget Moynahan, announced she was pregnant soon after they began dating in 2006.

She said: "It was definitely a surprise for both of us. In the beginning you're living this romantic fantasy, you're thinking, 'This can't be true, it's so good!' And then, 'Whoops — wake-up call!' "

Bundchen had only been dating Brady for around two months when Moynahan discovered she was pregnant and admits she considered dumping the athlete after hearing the news.

Bundchen told Vanity Fair magazine: "It was a very challenging situation. Obviously, in the beginning of a relationship it's not the ideal thing.

"You question at times, 'Should I stay here? Maybe you should work this out.' But when people break up, it's for a reason."

The 28-year-old beauty is glad she decided to stay with Brady and says the rocky patch brought them even closer.

Bundchen quickly bonded with Brady's son John, who is now six months old, and treats him like her own child.

She said: "I understand that he has a mom, and I respect that, but to me it's not like because somebody else delivered him, that's not my child. I feel it is, 100 per cent. I want him to have a great relationship with his mom, because that's important, but I love him the same way as if he were mine.

"All this was a blessing. It made me feel more in love with Tom, it made me realise who he was."