Am I too old?

Alison
I'm 44 years old and have three daughters 23, 19 and 14. I recently came engaged to an Aerospace engineer who wants to have a child of his own bc he doesn't have any (he's 54 ). Do you think that this is a bad idea given our ages? We can take care of financially and emotionally a child, but would it be fair to the child to have older parents?