Behaviourial Issues

by DL
(NY)

So cute when sleeping!

We recently rescued a 4-month-old male GP. At first he was very calm and sweet. He was doing amazingly well with potty training and playing fetch and working on his chew toys. Well, we found out quickly that he was actually sick with parasites and kennel cough. After getting him better and the weather cooling off, he has become much more active, including adding some unwanted behaviors very suddenly. He started jumping on us and that quickly turned into trying to mount us. He's doing this ALL THE TIME now! And to make it worse (he's teething, of course) he is constantly biting/chewing on us. He has broken the skin a few times. We have had to separate him from our daughter, who adores him and is sad that she can't play with him. The behavior appeared and escalated so quickly that it's difficult to even work with him on improving because the mounting and biting is so constant and unrelenting. To top it off, he's gone from almost potty trained to peeing wherever and whenever he feels like it with no warning. No sniffing around, nothing. Chasing his ball one second and peeing the next, even with regularly scheduled trips outside. We are using positive reinforcement and redirection to try to train and improve behavior (he has learned sit and to come when called but won't stay sitting so we were working on lengthening the sit time before all this started). He does not like being corrected in any way and will come back at us twice as hard if we do any kind of correction like yanking his leash. We do try to ignore him when he has bad behavior but this requires babygating him as he will just follow us around mounting and biting constantly! We want to do more walks but he frequently refuses and lays down, refusing to walk. I literally had to drag him home with all four legs out, belly on the ground, but he's getting too big for that now. How do we turn this ship around and get him back on the right track?! Will this behavior subside with an end to teething and neutering at 6 months? Thanks!