Daughter Wants Another Sibling

My (34f) daughter (6) has been asking me to have another baby and it’s becoming unbearable. She has a little brother (4) and even trying to rationalize why I can’t have anymore babies has created meltdowns nonstop.

I have epilepsy and I developed it while I was pregnant with little brother. I have them somewhat controlled, in that I have 1-2 every few months, but I’m on LOADS of medication to keep them from being more frequent. Without scaring her, I’ve explained that I can’t have babies with the medicine I’m taking, that I got really sick when I was pregnant with her brother, that I can’t stay healthy if I have another baby, etc. but nothing is working. I’m at my wits end trying to be nice about it…..