This isn't really fitness-related, but I thought it was interesting nonetheless. Did you know that baby talk actually helps babies learn faster?
A 2007 article posted by the editors of The Bump (http://www.thebump.com/) states, "Even though baby talk might make you cringe, there is something to it. A 2005 study found that speaking to infants in that high-pitched, sing-songy voice may actually help them learn faster. That’s because baby talk also usually involves slowing down your speech and exaggerating sounds, making it easier for your little one to distinguish words and pick up speech patterns."
To me, this makes sense. Parents adjust their manner of speaking to their children based on stages. Here's an example: When your four-year-old does something wrong, you most likely will get down to her level and explain why what she did was wrong. You wouldn't fill your lecture with huge words, because then your point would be lost with her.
In addition, baby talk seems to be universal. Here's an interesting article: http://www.eurekalert.org/pub_releases/2007-08/afps-bti082107.php