Sarah Ferguson's pop star friendship

Sarah Ferguson has become friends with Robbie Williams.

The Duchess of York - ex-wife of Britain's Prince Andrew - and the Take That star hit it off after meeting on mobile phone tycoon John Caudwell's yacht while they were holidaying separately in the Caribbean.

A source told The Sun: "Robbie and his wife Adya really hit it off with Fergie. They were all on John Caudwell's yacht and chatted for hours about all sorts. Robbie's been telling everyone how much he likes her."

Robbie has even given Sarah and her two daughters with Andrew, Princesses Beatrice and Eugenie, an open invitation to his Los Angeles home.

The source continued: "Robbie's told Fergie and the girls they can visit him and Ayda in Los Angeles whenever they like. Robbie says they'll be friends for life."

It seems Sarah is in need of all the friends she can get after it was revealed she hasn't been invited to the wedding of Prince William and Kate Middleton on April 29.

It was widely thought she would attend the nuptials at London's Westminster Abbey but she hasn't made the 1,900 guestlist.