[Nancy1999]

So much of it depends on the dog and when you get him neutered. The hormone testosterone is responsible for some of the behaviors, marking and humping, and while the testes make the bulk of testosterone, the adrenal glands make some, as well. I would recommend getting the dog neutered around 7 months before the testes start making massive doses of testosterone. Puppies will hump really early; there are many different opinions on why they hump. Some say it's a sign of dominance or they're bored or anxious. One of the breeders said that humping even helps the testicles to drop. I've never seen Joey's "lipstick", and he stopped humping after he was neutered. Concerning marking, so much of that depends on whether you will have other dogs visiting your house, since the adrenal glands make testosterone in males and females, both may mark, if they are around other dogs. The scents of other dogs get the adrenal glands to produce testosterone, and this in tern, promotes marking.

My son's male Maltese had visited my home many times before I got Joey; he never marked and never even lifted his leg to pee. He was at least 3 when we got Joey, and even though Joey didn't, at the time, raise his leg to pee, Baxter started raising his leg. So it wasn't seeing another dog raise his leg and imitating the action, it was the smell/scent of the other dog, that triggered Baxter's adrenal glands, and this caused him to start lifting his leg.

I've read that a boy and girl get along better than 2 girls.