This bug landed on our bouncy castle and was raising it's back to try & sting or attack my baby girls foot .
Could someone tell me what it is & is it dangerous ?
It's some sort of staphylinid beetle, but there are lots with that colouration. I can't ID it to species, maybe someone else can. Although they arch their tail ends over like that it's just threat. They can't sting and I've never been bitten by one - although I wouldn't like to get my finger too near a devil's coach horse (a BIG staphylinid). Personally I wouldn't worry about it.
It is one of the rove beetles (Staphylinidae). They are not really dangerous (like earwigs, they can look 'nippy' when their raise their claspers). The larger ones, if provoked enough, can give a bite, but they cannot sting.