Internet Blows It Again: Patty Duke and Quaternary Cousins

Last week, I laid into the Internet for not containing, in the open stacks, a note that Walter Cronkite stood up from the anchor desk for the first time while delivering his Watergate reports.

I do not live in the land of reality shows, so I hadn’t seen or heard of Extreme Sisters until it was pointed out to me by the Washington Post. It is a show which features a pair of identical brothers married to identical sisters, with one boy each, 8 months apart in age. Theirs is a quaternary marriage, of which only about 250 exist in the world. Their boys are quaternary cousins.

This has probably already rung a bell for most of the readers of PSACOT. In case you can’t quite put your finger on it, the setup of the Patty Duke Show (1963-66) was a quaternary marriage that produced quaternary cousins: Kathy and Patty.

In the way of 60s sitcoms (eg. Beverly Hillbillies and Gilligan’s Island) the theme song reminded you of the setup each week. In case you’ve forgotten it, here’s a blast from the past:

But they’re cousins
Identical cousins all the way
One pair of matching bookends
Different as night and day
Where Cathy adores a minuet
The Ballets Russes and crepe suzette
Our Patty loves to rock and roll
A hot dog makes her lose control
What a wild duet…

Since all practicing journalists are children, there is not a single mention of The Patty Duke Show in any article about Extreme Sisters; not even a mention in any culture blog that has been crawled by Google. Probably shouldn’t be a surprise since most of the writers’ parents hadn’t been born yet when the show was on the air, and it has never been big in reruns.

Comments

[Daniel Dern]

One of my doctors shares a practice with his twin brother.

And they are married to twin sisters.

[Robert E. Malchman]

I read that researchers got a whole group of these families together to study them. They called it The Quaternary Mass Experiment.