Sir Paul McCartney has hit back at critics and defended his wife Heather Mills.

The Washington-born former model has faced constant criticism since marrying the former Beatle, 25 years her elder, and accusations she and his fashion designer daughter do not get on.

But McCartney has answered back to critics. He said: "I'm not some stupid fool who fell for someone who looks good.

"Heather's a good person who does amazing things to help people. We are a normal family trying to do normal things."

Heather lost her left leg in an accident with a police motorcycle in 1993. Since then she has worked with amputees. McCartney praised her charity work.

He said: "She actually bothers to get up off her backside and do things to help people. She can make young girls who have lost a leg get their confidence back. I can't do that and there are very few people who can.

"A few months ago this 13-year-old girl was pushed in front of a train by some yobs and lost her leg. As soon as Heather found out we went up to Liverpool and Heather took her for swimming lessons. She gave that girl the confidence to carry on."

McCartney met Heather in 1999 and married her in June 2002. Since meeting, rumours have flown around saying she and Stella McCartney, one of Paul's four children with late wife Linda, dislike each other.

He said: "I'm sick of people saying Heather and Stella don't get on. The truth is they do. We're a normal family now, we've got a baby daughter and I don't want her being brought up into this. My wife is a good person."