Dd (2) has taken a liking to sleeping in the spare double bed in her room instead of her cot bed. We put her in cot bed and when check on her she is in the double bed. Does anyone let their child sleep in a double bed? Is it safe?
My dd has a double bed - although she was older than yours when we put her in it - probably around 4. I don't see that it can do any harm (other than making them used to having lots of space which can be a downside if you need them to share with a sibling on holiday or something).