"If you look at under the reign of Fauci for 40 plus years, where childhood chronic diseases and illnesses have gone from 6% to about 54% as we've added more and more layers of shots onto those schedules. And again, they'll say 'Correlation isn't causation.' Well, not a single childhood vaccine was ever tried in their clinical trials against placebo."
https://twitter.com/VigilantFox/status/1629888923282427912?s=20
Do they contribute to delayed speech in children?
Yes.
I have not heard that, but if they cause autism or affect the pineal gland which in turn affects IQ, I would surmise it may. It could also be a contributing factor due to mothers who take a variety of shots during their pregnancy: flu, rubella, Covid. Since every body is unique, who knows how each child will react due to maternal factors such as smoking, alcohol, drugs, work environment, vaccines, etc.