So I guess the "joke" here is that if you bring in anyone from the Outside to meet the Family, that Outsider can expect to be greeted by absolute silence- including the sudden muting of any music that happens to be playing and hell, while we're at it, the freezing of any cooking sounds that happen to correspond with the Outsider's arrival. Silence, and very cold, unfriendly stares from every member of the Family who will treat you exactly as if you've just stood up at the local Kingdom Hall to announce that you are in fact an Apostate and just came to let everyone know they are in a cult.
The silence and the threatening stares will only end when, and if, the Patriarch hands you a glass of Minute Maid Fruit Punch and bursts into laughter worthy of any escapee from Beldam Asylum. And when the rest of the Family joins in, well....if you hang around to actually drink that fruit punch, you must really like that girl or really like the idea of being "accepted" by this truly weird family. I mean, it's one thing to meet the Crazy Uncle We Have to Invite first. It's another thing entirely for that Crazy Uncle to actually turn out to be your girlfriend's dad and the role model for everyone else in this group of lunatics who somehow include your girlfriend. I'd start to wonder what I got myself into, and if there was some kind of Get Out deal at work here. In any case, I wouldn't drink that fruit punch, and I'd remind myself of that old saw "marry the girl, you marry her family."
(By the way, these people really like Minute Maid Fruit Punch...I mean, it's not TERRIBLE, but...there are a lot of better-tasting drinks out there. Seriously.)
*yes, I know it's not Kool-Aid. But it wasn't Kool-Aid at Jonestown, either.