Need Help With SCREAMING Baby. ?

Wow. I'm sorry to say it but I think you have tried everything. I always feel so guilty letting mine "scream it out" but maybe it is the only way. Crying won't hurt a kid but it can nearly kill a parent/caregiver. I would just lay him down and check on him frequently. Make sure everything is fine, clean diaper, not hungry, nothing poking him (like in his bed or clothes.) Realistically you can not hold him for 2 hours while caring for 2 other children. I would say however it sounds like you are doing a great job and not really the problem. You have to talk to the parents and encourage them to deal with the problem. Tell them how difficult it is to deal with the other 2 children when you have to hold an infant all day long. They need to commit to getting him out of their bed and into his own. Nine months is old enough. He is probably a little chunk to hold for that long too huh? I really feel for you. I would recommend you take or rather his parents take him to his pediatrician...maybe (I doubt it, sounds like he's just spoiled) there is a reason why he doesn't want to lay down like stomach problems or something. It never hurts to check and see. In the end just be strong and if the parent's don't mind let him cry a little and see if he won't come around. Good LUCK.