Gisele Bundchen and US football star hubby Tom Brady are expecting their second child together, a source told Us Weekly.

This comes amid much speculation after the slim Brazilian supermodel was recently spotted with a slight bump underneath her sweater at a Rio de Janeiro event.

The source said Bundchen, 31, is now three months' pregnant and the couple are "really happy".

They have a two-year-old son, Benjamin, together. Brady, 34, has another son Jack, four, from a previous relationship, with actress Bridget Moynahan.