Macca: No, it's a girl!

Sir Paul McCartney and wife Heather were "ecstatic" today after becoming parents of a girl called Beatrice.

The former Beatle became a father for the fourth time at the age of 61 when the child, weighing 7lb, was delivered by emergency Caesarean section three weeks early.

A statement issued by the couple said: "Heather and Paul McCartney are delighted to announce the birth of their baby daughter. Both she and mum are doing well. Paul and Heather are ecstatic with the news. They said, 'She is a little beauty and we couldn't be prouder'."

They said the girl was named after Heather Mills McCartney's mother Beatrice and Sir Paul's auntie Milly who helped him get over the death of his mother when he was 14.

The couple added: "Our immediate family were told the news right away and are all as overjoyed as we are at the early arrival of our little bundle of joy'."

Beatrice is 35-year-old Lady McCartney's first child. The baby was due in November and a Caesarean had been planned for the middle of next month. But the operation had to be brought forward.

Former model Lady McCartney lost a leg in a road accident in 1993 and is understood to have steel plates fitted in her hips which would make natural childbirth difficult.

She had Beatrice at the Hospital of St John and St Elizabeth in St John's Wood on Tuesday evening. Sir Paul was at her bedside all day yesterday.

It was initially reported in the Daily Mirror that they had had a boy. A spokeswoman for the hospital said of the couple: "They've got a good sense of humour,"

It had been feared that Lady McCartney would not be able to have a child. She has suffered two ectopic pregnancies and cancer of the uterus.

In a TV interview with Michael Parkinson in March, she said: "The chances of me getting pregnant are about that much" - and held up her thumb and finger an inch apart. There had been speculation earlier this year that she had become pregnant, but the couple waited more than three months before confirming the news.

Lady McCartney recently described their joy when they found she had conceived. She said: "He came out and I showed him the test and he just went 'Oh' and we both started crying."

The couple married in Ireland in June last year but their relationship has been troubled by speculation about a rift between them and Sir Paul's children by his late wife, Linda. In particular, designer Stella McCartney's relationship with her stepmother is said to be strained although there have been comments by Lady McCartney that they get on "brilliantly".

Stella, who is just four years younger than her stepmother, refused to add her public congratulations after the announcement of the pregnancy.

It is understood that Stella was also upset recently at the way Lady McCartney has agreed to become the new face of the charity PETA (People for the Ethical Treatment of Animals). Linda was one of the charity's most vocal campaigners and Stella continued her work.

As well as Stella, 31, Sir Paul has two other children - Mary, 33, and James, 25. He also has an adopted daughter, Heather, 39, from Linda's first marriage. The Beatles star's first wife died in 1998 from breast cancer. They had been together more than 30 years and were devoted. It is for this reason that it is understood Sir Paul's children are concerned about the influence of his new wife.

The children told friends they feared the birth of a child could estrange them from their father. Sir Paul is worth £760 million although issues of inheritance are not believed to be a concern of his children.

Lady McCartney, who works for a landmine charity, has come under fire for her colourful past including topless modelling. But Sir Paul said: "Obviously, I wouldn't have married Heather unless I though she was a really great woman, and very, very impressive."

Lady McCartney's father Mark Mills, 62, said today: "This is my first one and it is a grand time for me and I love the new baby." Mr Mills, who has suffered a stroke, fell out with his daughter in recent years. He said: "I am very proud of my daughter and what she has achieved."