There is nothing facetious there. The part about not crying could be a slight exaggeration, but not a major one. My mother was clear that it was extremely rare for me to cry except at bath time, and that my older my sister almost never cried except at feeding times. She did mention one other time when I was crying and being fussy though; when she first took me to get my picture taken, I cried until after they gave me a soccer ball to hold. (As a side note, having my picture taken at that time automatically entered me into a national "Cutest Baby Contest," which I won. They wanted me to be a model or child actor, but my mom did not like that idea.)
Non-crying babies are by no means unheard of. The Souix where known to abandon infants that cried more than once when the tribe was on the move, so quiet ones were the norm there. The poet Virgil and several other literary greats were said to have not cried as infants. Children are born with many personality traits they keep as adults. Not crying as a baby is an early sign of strong introversion, and/or an autism spectrum disorder.