As Bloomberg congressional reporter Greg Giroux notes on Twitter, the younger LaHood joins 19 other members of Congress whose parents also served in Congress. The list includes senators Rand Paul, Lisa Murkowski, Shelley Moore Capito, and Tom Udall, as well as 15 other House members.

But why stop with children? Michigan congressman Sander Levin is the brother of recently retired senator Carl Levin, and Dan Kildee, also of Michigan, succeeded his uncle Dale Kildee in the same House seat. It also wouldn't be fair to leave out the members who serve in their spouses' former seats, including Doris Matsui and Lois Capps of California and Debbie Dingell of, yes, Michigan (Is there something in the water of the Great Lakes that induces political nepotism?)

Add to that those members of Congress whose parents and other kin have been elected to statewide office like governor, and American politics is starting to look like a real family affair. It's a feature (or a bug!) of both parties.

So perhaps we shouldn't be surprised that two of the potential presidential candidates, one in each party, is directly related to a former president—and in Jeb Bush's case, to two former presidents. Both Bush and Hillary Clinton would fit right in in Washington.