J.C.
Hi! I have one of those cushioned potty seats that fit onto the toilet. You know those catchers that go on potty chairs to catch boys' pee? Well, if you can find one that comes out, they will actually fit into the crevices of the cushioned potty seat at the front where they can catch their pee. That's what I do. My boy now stands up, but for the longest time I would take him myself and stand behind him. I would put my legs against him to guide his body forward a little and then hold onto his shoulders with my hands so he didn't fall forward at all. Now, since he's used to that position, he goes by himself and leans forward while he stands at the toilet so that he's "aimed" at the water. I think it just takes learning the proper way to stand, so try doing the standing behind him to teach him the best way to do it. 18 months....you go girlie!