Trouble with small dogs

[Suzanne H]

My sister has two female springer puppies three months younger than Otto and they came to visit last night and Otto cocked his leg and peed on one of them.

They were being very submissive with him but he's very rough with small dogs so had to be put in his crate. But he was the same with my friend's male Bichon and tried to hump him.

There is no problem with big dogs, because obviously he judges them against himself. He gets very excited, and calms down but doesn't with small dogs.

His hormones have obviously kicked in but take it, it's just correcting the behaviour...it's like he becomes so excited you can't stop it.