Open Question: How old is is old to have a child?

I currently have a nine year old son who is an only child. I’m twenty eight years old and would like to possibly have a little girl some day. I know I wouldn’t like to commit to having her now mainly because I had my first and only child when I was eighteen years old and would like to start a business, own a home, an get even more edication first and have some freedom first.My child will be eighteen when i’m thrity six years old.Would it be consitered to late if I had a child at fourty five cause i’m not willing to have a child until later in life?I have always dreamed of having a daughter.