Kate and Sam wed

There was no fanfare, no glitz and no VIP guest list. Just a bride, a groom, three friends . . . and the bride's toddler daughter.

Kate Winslet and Sam Mendes yesterday let the world in on the best-kept secret in showbusiness. They married two weeks ago in the garden of a sun-kissed villa in the West Indies.

Not even their parents knew it was happening. Mia, Miss Winslet's 21/2-year-old daughter from her first marriage to film executive Jim Threapleton, was the only family member present.

The 27-year-old actress said last night: 'We hadn't been planning to do it, but we

thought it was rather a good idea, so we just did it.'

The couple, who have been dating for 21 months, hired the Caribbean villa for four weeks in early May following the opening of Mr Mendes's production of the musical Gypsy on Broadway.

A friend who flew out to join them said: 'They hired a private house where they could have some peace and quiet. They were finally in a place where they could be private and it got them talking and it just transpired that they wanted to marry.

'There were three of us who just happened to be there and we got roped in. It was a breathtakingly beautiful day.

'They had no idea in the world that this would happen.'

The couple told their respective families when they returned to London.

Miss Winslet's mother Sally said: 'We knew nothing about

it until she came home and told us she was married again. I don't think it was planned at all. They found themselves there and just said "let's do it".'

Her father Roger added: 'We are very, very pleased for Kate and Mia. I am very happy to have Sam as a son-in-law and, more importanly, Kate is over the moon.'

The couple, both born in Reading, met towards the end of 2001 when Miss Winslet went to Mr Mendes's London theatre, the Donmar Warehouse, to discuss a part in a double bill of Uncle Vanya and Twelfth Night. Her marriage to Mr Threapleton had recently ended after less than three years.

At a party last year, Mr Mendes's mother Valerie looked at Miss Winslet and said: 'She's the one. Sam has never been happier.'

In February Mr Mendes, 37, Oscar-winning director of American Beauty, paid tribute to Miss Winslet as he made theatre history by becoming

the first triple winner at the Laurence Olivier awards with his Twelfth Night/Uncle Vanya double bill.

Accepting the prizes he said: 'I want to thank my partner Kate, because these are two plays about love and it helps, when you direct them, to have some personal experience.'

Seeing the couple together over the past 18 months, it has been clear they are very much in love, but that both were wary of marriage.

Mr Mendes had given such commitment a wide berth, possibly because his own parents broke up when he was five.

He and Miss Winslet announced last month that they were taking a 'gap year' from film-making to travel the globe, surprising many in the industry as they are both very much in demand at the moment.

It prompted speculation that they may be planning to have a child together.

Miss Winslet has spoken of her desire to have a family with Mr Mendes and friends describe her as 'very broody'. Mia is said to have developed a warm friendship with the man who is now her stepfather.

The newlyweds were in Europe last night.