I have a long hair Dachshund about 16 months old. He's mostly potty trained, to go outside, however, every time he gets really excited to see someone, he loses control and pees all over the floor. I don't think he's doing it on purpose and I can't really punish him for it, but what can I do? I mean, shouldn't a 16 month old dog be able to control himself by now? My best friend and "old" dog did this when he was a puppy too, but quickly grew out of it.