It's not weird at all to sleep with your kids, I would say every once in a while, just not a every night thing. When it becomes a habit the kid loses independence and so do you, actually, you start to depend on each other in ways you shouldn't anymore at these ages. And it's NEVER safe to Co sleep with an infant, never, so please don't do that with your new baby. If you can't sleep without him and are up all night and he is too, ask your Dr first of course, but both of you could try melatonin for sleep.
I have a 2yr old that I have to have her next to me or I can't sleep. I know the feeling. Ive tried to break the habit of her sleeping in the bed with us but I can't do it. I'm 16w with baby #2 and I feel like I'm gonna need a bigger bed cause that ones probably gonna be sleeping with me to, I'm hoping I can start that one sleeping by themselves but I don't think I'll be able to.