Buster went to Vermont with his father. Along the way, he learned about the people they were going to see. The first cue was the phrase, "She lives there with her partner, Gillian."
Then the camera strolls up to the door, and we meet a woman who is supposedly an old friend of Buster's mom. She shows them in and introduces them around. While Buster is looking at family pictures with the daughter, Emma, he asks about a picture of the two moms. "Isn't that a lot of moms?"
The story then moves downstairs where the brothers are boxing with a heavy bag. They take a moment to explain that one is a step-brother while the other two are directly related.
That's pretty much it.
As to devising a scale? I'm not sure how to mark the units.
If showing a child rape-pornography, for instance, constitutes a 100% harm factor, I'd estimate the following:
Bush speech: 50%
Dazed and Confused: 45%
Sitcoms: 40%
Card-game cartoons: 33%
War/combat cartoons: 30%
Sponge Bob Square Pants: 20%
Teletubbies: 0-10%
Postcards From Buster, "Sugartime": 0-1%
Then again, children with two moms is what touched off the gay fray in Oregon over a decade ago. Some things never change.
I think the politically-sensitive fear would be that children would form an abstract bond with a television character, such as the children of this Vermont family. As such, when the question comes to the viewing children later in life, they will possibly have greater sympathies to the
children of gay families: Don't hurt Emma's parents because it hurts her.
And God only knows, a compassionate child is a threat to national security. At least, in "middle America".
Seriously, if Spellings hadn't opened her trap, I might not have noticed this episode at all. Then again, this sort of controversy is the price we pay when PBS changes from "Community-Cooperative Ready to Learn Grants" to "Ready to Learn/No Child Left Behind Grants". It seems our Education Secretary would like to leave children of gay families behind.