I don't think Aaliyah had a baby before she died because she was at her rock the boat video shoot which ended up being her last video shoot , & I guess nobody knew she was pregnant because she looked was so skinny although she was going to marry Damon Dash but that never happened because she ended up dying.
Nobody even knows if she was but her so we will never find out!
No she did not have a baby before she died,but in one of her interview she once said she does want to have family one day, but that day will never come (r.I.p).