E.W.
First girls are different than boys. Girls talk sooner. Two it sounds like you never noticed it before the doctor so I would guess you felt like he was developing okay before that. I think doctors just ask routine questions to document a baby's progress. Autism is so much in the news and parents are so worried of having child like that, that I'm sure by asking specific questions as babies grow they are able to look back on all their documentation and determine if a child fits that category. At your child's age it is hard to diagnose that but at 2 years old it would be easier. SO don't worry and enjoy your child AND DON'T COMPARE HIM TO YOUR OTHER CHILDREN. Younger children are different than older children. I have 4 kids and they are all different and also remember if you and your spouse are not talkers don't be surprised if your child is not a talker. Relax and enjoy.