I have 3 boys, 1 3yo fix and 2 2yo not fix yet. All 3 would try to do that with my female when they were lil under 1 yo but none of them do that now.
When I would see them getting too excited from playing or smelling my female I would calm them down and distract them with something else like a treat or start to brush them. Sometimes their lil wee wee comes out and I pick them up and tell them to put that away and blow a lil cold air to make it go back in and thats all.
I do still have to tell the 2 lil ones everyday "leave Buffy alone" because they want to smell her hoo hoo and taste her pee
(don't ask I have no idea why)
But there is no humping here TG!