Separation anxiety

Anyone else’s babies have separation anxiety? My little one is good all day as he’s with me either at home or if we go out with others. I’m lucky that if he can see me or knows I’m there I am able to get things done and put him down so he doesn’t have to be attached to me constantly. However when dad comes home and wants to spend time with him and I leave the room to do jobs etc he cries and doesn’t settle. Dad will try to comfort and hug him the way I do but again he just won’t settle. Before this I left baby with family members from a young age and he’s always been fine. I’ve just noticed this last week or so.. he is 3 months old. He also at night doesn’t cry but when I put him down to bed he will lie awake until I get into bed next to him then go to sleep even if this is 10 minutes, 1 hour it’s very strange. I’m therefore dreading the transition to his own room when he’s bigger. Any suggestions?