Girls I need some help my little boy is a nightmare at sleeping at night I put him down to sleep and…

Girls I need some help my little boy is a nightmare at sleeping at night I put him down to sleep and he stays asleep but as soon as me or me and my partner get in to bed he wakes up and wants to sleep with me im stuck of what I can do coz I've tried everything he can't go in with his sister either Coz she sleep walks and still wakes up