Locks, all our bedroom doors have locks and both my kids went through trying to get in bed with me and their bioD when they were little. First in between us, then next to me, then the end of the bed then the floor next to me. At 4 I started locking the door ( didn't mind I never woke up just cuddled up with them ex always woke up even if they were on the floor her just knew they were there) Once we had the door locked for about 2 weeks never had a problem unless they got sick or there was a bad dream and they would then wake me up to take care of them.
My bs went through climbing in bed or asking to sleep with me just after his dad and I split I let him for a bit (at 8 yr old yes I know) but I realized we were both using it as a crutch and put a stop to it. He stopped asking after I explained to him how it wasn't good for us to heal that way and that grown up beds were for grown ups only. He said "I just want you to not be lonely and crying" (I tried not to in front of them but I knew they knew) I told him I understood but I was a grownup and we would be okay and as the mom it's my job to get okay again on my own so I could help them be okay too.
SO's kids don't get in bed with us never have they will wake us up if they need something and go right back to bed, because we kept the door shut when they first started staying and let them know it was a house rule no kids sleeping in grown ups beds.

Mmmm yes, I knew OH had a history of allowing SS8 and SD11 to share his bed (after he left BM) so when we moved in together I laid down the law on that one - that is OUR space, and I don't want any kids photos there, kids in MY bed or my space. (oh - the photo thing - there are many pics of all the kids all over the rest of the house, but I don't want ANY of them in my face while we are "intimate" so it remains "our" private space)

Found out that the first few weekends he was allowing SD11 to jump in my side of the bed and watch TV with him on Saturday mornings as I leave by 8am to get my DD's to ballet. And SS8 was always in the room attempting to come between SO and I.

Another serious conversation - made it clear to SO that that room is OUR space. NO kids - it is where we go to be alone, to talk, and it is where we are intimate - I pointed out that our sex life was going to seriously suffer if either of us had the image of that bed as space he shared with his kids.....

Worked a treat Kids no longer allowed to hang out in our bedroom. They do enter the room (after knocking first) if they need us and we are in there, but that's a different thing.

First of all...EWWW :sick: I'd never EVER let the skids sleep in our bed with us! The skids aren't allowed in our room, period...unless we give them permission. It's our private space and they know to respect that. When we first moved into our current house, the skids didn't want to sleep in their own bedrooms (separate rooms in the basement, but very nicely done thanks to grandpa who spent thousands trying to make the space nice and cozy), so FH let them sleep on the couch in the TV room. I finally reasoned with him that they have perfectly fine bedrooms in the basement and that's where they should sleep. God forbid if BM found out that they were on the couch overnight - she would've blown a gasket and bitched about us not providing proper bedrooms for them! For safety and privacy reasons, your SD SHOULD sleep in her own room. Just maybe with the door open a crack in case she's scared to be by herself.