Thanks for responding Vickie. My son is very slow riding with the training wheels In fact,I walk beside him. He has trouble on even the slightest incline. When he picks up speed going down even the slightest hill, basically what most people would refer to as flat, he tends to panic and either brakes or falls over. I don't know if he could manage a trailer but am thinking that I would provide most of the balance but really don't know how sturdy they are. Again any help would be appreciated. thanks