Don't forget to call your parents.

If you don't, David Thornburgh found out Monday, you just might get a surprise phone call from a reporter: Hey, did you see your dad filed this brief with the U.S. Supreme Court?

"No. That's very interesting," said Thornburgh, laughing. "My mom called over the weekend. … It strikes me I should probably check in with them."

Thornburgh is the head of the Philadelphia good-government group Committee of Seventy, which advocates ending gerrymandering by reforming the redistricting process. He's not a fan of the previous Pennsylvania congressional map, widely considered an extreme partisan gerrymander drawn to favor Republicans, and thinks the new one is better.

His father is Dick Thornburgh, Republican governor of Pennsylvania from 1979 to 1987 and U.S. attorney general between 1988 and 1991. He has filed a brief, along with the chair of the Republican State Leadership Committee, asking the U.S. Supreme Court to block the new map.

The same new map that his son's committee called "a clear improvement" over the 2011 map.

"Boy, is my face red," David Thornburgh said Monday, still laughing.

It's not exactly a family feud; the Thornburghs agree that the way districts are drawn must be changed, the younger one said, and worry about the confusion that has arisen since the new map was released. (Dad was unavailable Monday, according to his lawyer, David R. Fine.)

"Because I've talked about this with my folks and my dad quite a bit, I think we at this point both share the concern that this has been a chaotic and confusing and distressing process that we prefer not to repeat again," David Thornburgh said. His focus is on reforming the actual process, not on fighting over the court's map; his father's focus, in the brief, is on the constitutional law questions raised by the court's actions, not the map itself.

Dick Thornburgh was careful to note in his brief that he and Bill McCollum, the former U.S. representative from Florida and state attorney general who chairs the RSLC, "take no position here on the suitability of Pennsylvania's 2011 redistricting plan."