When she announced her arrival five years ago with the huge hit single Complicated, Avril Lavigne came across as the pop world's brattish little sister.

Her face daubed with black eyeliner, the then 17-year-old was the surly, snarling antidote to clean-cut pop princesses such as Britney Spears.

How times have changed. With Britney now lurching from one personal crisis and fashion disaster to the next, Avril is the disaffected skater-girl who has cleaned up her act.

With her flowing dark locks now bleached blonde and a wedding ring on her finger, the Canadian has grown up fast.

But while age and marriage (to Canadian rocker Deryck Whibley) have undoubtedly mellowed Avril, the 22-year- old hasn't lost her edge completely.

Sitting in front of me in a hoodie and sneakers, she is still every inch the rock chick with a high-octane album to promote.

"I've changed a lot over the past five years," she says. "When people first got to know my name, I was just a kid.

"I was a very young 17-year-old and I came from a small town. I had different clothes and a different hairstyle. I've gone from being a tomboy kid to being a woman."

When I first interviewed her, at the height of her initial success, Lavigne gave the sullen answers of a spiky teenager.

Now, even though she is reticent to reveal too much about her personal life, she is far more polite and forthcoming.

"Everyone can see the changes in me,' she agrees. 'But underneath I'm the same. I'm not sitting here in a Chanel dress.