Sarah Harding is doing "really well".

The Girls Aloud star entered rehab earlier this month to receive treatment for depression and alcohol addiction and bandmate Kimberley Walsh says she's responding well.

Kimberley - who is currently playing Princess Fiona in the West End production of 'Shrek' - said: "I don't want to go into detail about Sarah, but she's doing really well. I hope that soon she will be well enough to come and see me. My contract's due to end in February."

While Sarah is yet to go and see Kimberley in action, Cheryl Cole and Nicola Roberts have and Kimberley is hoping Nadine Coyle will follow suit.

She told new! magazine: "Cheryl and Nicola have seen it and they loved it. They texted me earlier to wish me good luck. Nadine will hopefully come and see me, too."

The 29-year-old beauty also revealed the group - who are currently on a break - are keen to work together again and would love to be the subject of their own musical.

She said: "A musical about Girls Aloud would be brilliant! It would work because it would have songs that are relatable. The girls and I have something planned for next year."