So I came to my partner about being an adult baby, only I know she struggles with what, in my head, I would expect mummy to do. She is more than happy playing mummy but I feel she asks me a lot of questions that you would not expect to have to answer while in regression, or that mummy would/should be doing automatically.
So here's my perspective on what mummy does with her child
Take control -
When baby is in baby 'mode', take control. Your child is vulnerable and does not know nor understand life (although level of understanding may vary on baby's age).
Again depending on age of your baby, speech may not be a strong point from your child. Do not necessarily try and make full conversations with them; and definitely, definitely, and again definitely do not try to talk about adult things. Honestly pretend that your child, is A BABY. 'Is [baby name] ok?' '[Baby name] want a hug?' - then back to no.1, take control and carry it through.
There's lots of games that you can play with your baby depending on their age. I won't say much on this as there are lots of ideas roaming around the forum already. Back to no.1; take control and invite them to play the game. Your child may be shy and not answer to you asking them whether they want to.
Diaper changes -
I got to admit, one thing that gets on my nerves is 'do you need a change?' 'Are you wet (yet)?'. Well as a baby, you're not gonna be answering questions like that, and nor are you really gonna care... And back to no.1 again. Check if your baby is wet from time to time, and if they are take them to one side to be changed. You do not need to ask your baby if they need to be, you're mummy, you make that decision.
Decision making -
Moving nicely onto this. You are mummy who is an adult, and baby is a baby. Baby does not make decisions. Baby knows what baby wants and may point to what baby wants. Try and 'listen' to your baby's needs, take some initiative as they have no awareness or cares in the world. Offer them their water cup when you think they're thirsty for example. Just do it.
I think the advice I can really give beyond this is pretend that your baby is a real baby. Try not to look at them as an adult in any shape or form.
If you have an any other ideas to help new mummy's treat their baby's I'd love to hear them.