no. My eldest was clearly autistic from birth. No eye contact, no interest in faces, no babbling, went rigid when you held him.
I didn't know that's what it was. I thought he didn't love me and I was a bad mother.
He was diagnosed at two and a half. The process did not take long. There was little doubt!
My youngest, who is 15 months younger than my eldest, developed 'normally'. In fact, he is the reason I went to the hv & gp with concerns about my eldest. He was so different. I just lost him one day. One day babbling, grinning, hugging, looking me in the eye. Next day - gone. That person didn't exist any more. He was diagnosed after he was 3
He regressed at about the time he WOULD have had his mmr - had he had it, I would have linked the two, no doubt about it. I would have been screaming from the rooftops that the mmr had done it! But clearly - since he never had it - it wasn't that in his case. In my case, I think it's genetic. There are clear autistic traits in several members of my family, myself included.
(neither of them had the singles until later anyway. my eldest was over 4 I believe)