Grandma70s, I think you must be me - that's exactly the problem I had with getting over the Mummy and Daddy thing. I felt ridiculous using those names as an adult, but Mum and Dad or first names were just not acceptable, so I had to avoid names altogether.
Our AC have refused our offer to use our first names, but DILs & SIL have always used them. Our DC, when little, always called our friends and their aunts and uncles by their first names, but this fashion doesn't seem to apply any more, at least to the DGC with their aunts and uncles.
I'm happy to be called by my first name, and won't mind if the DGC ever start to do it. After all, it's the only name I've got of my own - my other name is just borrowed from some man!