I agree with the point of view you have and you are the best judge of what your daughter can handle. I'm sure I saw a topic on a mods sig about siblings at birth???

Me personally I couldn't have DS at the birth, for me I need to be in my own space, head and body and I couldn't have done that with DS, I would have been primarily caring for him IYKWIM - even if someone else was there, I know in the end it would be me he would want to read, colour in, talk to etc

I wish you all the best for your beautiful birth and hope you get some good arguements for your mum