dd sleeping on side

[kbaby]

Hi,
I know I may be panicking a bit but hope you can all help.
DD has just learnt how to roll over, I was pleased but now shes started doing it at night. I lay her on her back and then when I check on her she has rolled onto her side. Last night I didnt sleep much as every little noise I had to check on her encase she had rolled on to her tummy and couldnt breathe. I have read that at 6 months it doesnt matter if they sleep on their tummy as the risk of cot death is reduced by then, but dd is only 15 weeks old. Do I just leave her get on with it or do I buy one of those things that keep her on her back while shes asleep. I have visions of her on her tummy face down on the mattress unable to move.
Thanks from a anxious mum.

Leave her to get on with it. DD was nrolling over at 12 weeks and buy about 20 sleeping on her tummy with her knees pulled under her chest. Both dd and ds still sleep like this. I remember mentioning to my health visitor who said not to worry about it. If they've got themselves into that position they can get themselves out of it!!!