What happens if a child wets his/her bed frequently, could that be a sign of diabetes?

Depends : Children can bed wet until their teens. Unless this is a new thing, it's perfectly normal. Bedwetting alarms can be helpful. There are medications you can use as well for an older child that is starting to get embarrassed. Of course if it's a new thing, he's losing weight & drinking more, having daytime accidents, fever, painful urination etc, that is a sign of something concerning