My niece, who has an IQ bordering on unmeasurable, at 8 months was sitting in her exersaucer and my brother said, “Bouncy bouncy bouncy!” and she bounced 3 times. He said that again, and once again, she bounced 3 times. At the time, she couldn’t “count” to 4, but 1, 2, or 3? Yep. She got it. That was the first indication we had that something was up. 
That’s a cute story, but how do you know that your brother didn’t know that when she bounced it would be exactly three times? She could have been doing that for a while, and he’d realized she’d do it three times if he said the word bouncy at all.
As for babies that’ll have a high IQ, haven’t they done studies to indicate that they have a higher level of alertness as infants than other babies? Like the ones referenced in this article. 5 Characteristics of a Gifted Baby
Good point elfkin477. Very helpful. Thank yopu all.
davidmich