We have an almost 4 year old son who was recently diagnosed with autism. We also have an almost 8 month old son that I'm concerned about autism lately. Does anyone have more than one child who is autistic? My 8 month old used to say mama and dada and used to mimick sticking his tongue out and making blowing sounds with his mouth but no longer does. He also doesn't wave goodbye or sit up on his own fully. I'm so unbelievably afraid he may be regressing. Is there anyone with a similar situation???