3 yr old waking up for 2-3 hours in middle of night!

[Loulou0]

My 3 year old DS goes off to sleep easily. However, he has always woken up at around midnight and got into bed with me. This has never been an issue as he previously just went straight off to sleep until morning. (And I quite like sleeping with him.) However, this last week or so, he has been getting in with me and staying awake/talking/kicking me/ messing about for 2-3 hours at a time before he eventually falls back to sleep. During the awake time, I have tried all of the tactics I know (bribery, reasoning, threats of punishment, promise of reward) to get him to lie down, keep quiet, close eyes etc
DH thinks now Is the time to try to make DS stay in his own bed and I did that last night, but ended up going back and forth about 12 times taking 3.5 hours!
We have a 6 week old baby too, so I am concerned that DS's change in behaviour is an emotional response to this - although I am doing everything I can to keep DS happy. He gets lots of attention and quality time with me, he loves going to nursery, he eats well and is happy and smiley during the day. DS loves the baby and on the outside he doesn't seem to have any resentment towards him. The baby's night feeds aren't affecting him as they are done on a different floor of the house.
Can anyone offer advice/tactics please to either A) get my DS to go straight back to sleep when he gets in with me or B) Stay in his own bed

Does anyone else think that this is the wrong time (with the new baby) to insist that DS starts staying in his own bed? I don't want him upset. DH is insistent and I am out of ideas.

Thanks

[Andcake]

Ds ( now 3.10) has always done this during big growth spurts. Tbh it's exhausting. My most recent solution is to put him in with do who is better at not interacting than me and ds is so bored he goes back off to sleep. I go and sleep in ds bed.

Another improvement was once ds could definitely go to sleep without me in the room as now I call out to him reassure then stay in my bed.