Girls Aloud party in their slippers.
The five girls celebrated Sarah Harding and Kimberley Walsh both turning 31 in November with big night at a hotel and after they danced themselves into the ground they asked staff to bring them some comfortable footwear.
Kimberley - who reached the age on November 20 - revealed: ''We had a bit of a wild one for mine and Sarah's birthday. I actually asked the hotel to get us some slippers so we could carry on dancing because our feet were hurting so much!
''We all had slippers on and were dancing. It was so much fun. It was a really good night.''
Sarah - who turned 31 on November 17 - added: ''It was a great idea, it's really quite fun (to wear slippers).''
The band have got back together after a three-year hiatus to celebrate their 10th anniversary in the music business, releasing a greatest hits album 'Ten' and announcing their 'Ten - The Hits Tour' for 2013.
In a joint interview with the entire band UK station BBC Radio 1, Kimberley said: ''I just think it's crazy that it's been 10 years. It just feels like yesterday, it really does.''
Sarah admits a recent encounter with some Girls Aloud fans made her feel really old.
She recalled: ''It's weird seeing your fans 10 years on. I met some out the other night and they were around 18 years old, and they're were like, 'You came and played at our school.' It made me feel really old.''
Despite all their success and years of experience, Cheryl insists she and her bandmates are still on a learning curve.
Cheryl - who enjoyed the biggest solo success of all the girls - said: ''We're still learning now, to be honest. The music industry changes so quickly and technology changes. When we started there was no Twitter, no Facebook, none of it was there ... It's like going back to the dark ages.''