My puppy is 5 months old and I'm wondering when he will reach sexual maturity. He isn't lifting his legs or marking territory, but just want to prepare myself for what to expect. He's our first puppy so I'm flying by the seat of my pants here. Ha ha. He does "hump" things, such as his toys, or even the air sometimes if he's feeling a bit over energized, but I tell him to stop and he usually does. Now, the other morning he got up on the bed with my husband and I after going outside to do his business and went right up to my husband's pillow and started humping his face! Now, I tried to tell him to stop but I was laughing so hard I couldn't get the words out, and my husband could not make him stop, even trying to push him away. I finally grabbed him and pulled him away but it was so hard to scold him. He just looked at me and wagged his tail. I don't think that he's reached sexual maturity yet, but want to prepare myself a bit, especially since that was a new thing. Any tips or advice would be great! Thanks!