Not sure what to do😩

My 3 year old use to sleep all night since he was 1 month old until he turned about 2 now he wakes up 3-4 maybe sometimes more night . I just bring him back to bed but once 5 am comes around he refuses to go to sleep unless it's in bed with me he will cry and keep coming back no matter how many times I bring him in there. I can never get a good night sleep and now I'm 9weeks pregnant and I just wish he would start sleeping all night in his bed.. Any suggestions on what I could do? He sleeps with a night light on too and he has no problem going to sleep at night in his own bed... I know I'm gonna have to wake up a lot  at night once the baby is born but I'd like to be able to get sleep in at night until then...