According to the on-line dictionary I have bookmarked on my computer, kvell is a Yiddish verb meaning "to be bursting with pride, as over one's family." The origin is given as the German word quell, pronounced the same way, which means Spring. No doubt all of that is very true, but it does not capture the combination of pleasure and smugness with which Jewish mothers advertise their children. [We all know the old joke about the Jewish mother pushing a pram built for two, who, meeting a friend, says "The older one is the doctor; the baby is the lawyer."]
I will give you an operational definition of kvell. In 1953, when I was elected to Phi Beta Kappa, following my sister in this honor by two years, my mother appropriated both of our Phi Beta Kappa keys and had them made into a pair of earrings for herself. [Inasmuch as her maiden name was Ornstein, which means Earring, there was a certain mad logic in the act.] Now that is kvelling! It was also, not irrelevently, a marker being laid down for her three sisters-in-law, all of whose six children were younger than Barbara and I. Top that! she seemed to be saying.
In future posts, I will from time to time kvell about my two sons, Patrick and Tobias, who are, you will not be surprised to learn, the finest sons any man has ever had, old Joe Kennedy not excluded.