With my first I had my DP, my mum, and my twin sister. Orignially It was just going to be my DP and my sister there with me only, but while I was in labour I really needed my mummy there.
They kind of took it in turns who'd have a break/nap, etc so it worked out well.

With DS2, I had DP and my mum. My sister was looking after DS1.

Good luck with your upcoming birth. I hope it all goes well.
xox