Do you think young toddlers can sense pregnancy?

My son is 20 months. I just turned 32 weeks pregnant and for the last week and a half he has been SO clingy and just emotional. Not like his normal self. He just wants to be attached to me and doesn’t want me to walk away where he can’t see me- when before he didn’t care too much. He also has been throwing a lot more tantrums and fits. All he wants me to do is hold him and snuggle him. Its like I can’t do anything and it’s wearing me down because he is almost 32 lbs!

I’m wondering if he can sense his life is about to change in a couple of weeks or if it’s just the stage he is entering? We don’t say much about the baby, just “oh you’re going to have a little brother.” Or “you’re going to be a big brother” but other than that we haven’t made a big deal or anything. We don’t even say those phrases often at all.

Can toddlers just sense pregnancy you think or is it more likely he just is entering a new phase?