My partners little girl is 6. She started staying with us every weekend when she was 3 and has had her own bedroom since she was 4 and has slept in her own bed at our house since then. Around the time of doing up her bedroom we spoke to her mum who said she still slept in bed with her, but she was going to decorate a bedroom for her and get her in her own bed before she started school in September.
Fast forward over 2 years and she still co-sleeps with her mum/nana/grandad at home and still does not have her own bedroom.
Everytime they go on holiday and we don't see her for a week we go back to square one of getting up repeatedly for hours in the middle of the night because she refuses to stay in her own bed.
So my question is, what age is too old to co-sleep? We feel like 6 is a bit too old now, and she should be able to self sooth and fall asleep on her own which she cannot do. Her mum says she doesn't want to upset her daughter and she'll start sleeping in her own bed when she's ready.
The most important thing to us is that she has consistency but we seem to be on very different pages with her mother.