Has anyone else's three year old started acting like a baby?

[Glow25]

Anyone one else's 3/4 year old start acting like a baby?
My lovely, active, polite, sociable 3 and a half year old has started acting like a baby.
She has hit all milestones, speech is good, physically strong, has friends at nursery but has suddenly decided at home she’s a baby.
Deliberately talking like a baby, asking to be carried, asking to be fed, asking to watch baby tv, watching a baby cup/ bottle.
if anyone can relate, is there anything I can do and when did it stop? 😂

Has anything changed? New room at Nursery or maybe a new sibling?

I have a three year old and a 1 year old and the older one has started acting a bit babyish - for example the baby will point and grunt at something and now my toddler will do that rather than just asking for something like he used to. It’s quite annoying! Sometimes he whines and talks like a baby too. I’m guessing it’s because the baby gets attention so he’s copying.
Do you have a new baby? Or has anything else changed?