Husband David, 33, recently revealed that they are trying for another child. The couple, who have sons Brooklyn, 9, Romeo, 5, and Cruz, 3, are hoping for a girl.
‘It's no secret Victoria's desperate to have a baby girl, and putting on a bit of weight can help,' a source tells the Daily Star.
Meanwhile, pals Tom Cruise, 45, and wife Katie Holmes, 29, babysit the Beckham boys at the weekend while Victoria was in London to launch a new clothing range.
Tom took the boys and his children Suri, 2, Connor, 13, and Isabella, 15, to watch Becks and his team LA Galaxy play the New York Red Bulls.
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