After the last Olympics I wrote a post about family traditions in sport -- quickly counting up how many of our medal winners had parents in the athletics/cycling/rowing business. I now discover that the House of Commons do the same exercise for MPs, much more efficiently, checking out their family histories. There was one survey in 2008 and another earlier this year. The first one covers just one generational links, plus husbands and wives. The most recent one (though excluding "in-laws") goes four generations back -- from which we discover that David Cameron is the great grandson of Sir William Mount (Con. Newbury 1900-1906, 1910-1922), that William Cash is the great grandson of the cousin of John Bright (Lib. Durham 1843-1847, Manchester 1847-1857, Birmingham 1857-1889), or that Harriet Harman is the great great niece of Joseph Chamberlain (Lib etc, Birmingham 1876-1885, Birmingham West 1885-1914).
If you just stick to sons and daughters, the figures are pretty much identical in 2008 and 2014. Counting one stepson, there were 21 MPS who were the children of MPs in 2014, and 20 in 2008. They were pretty well balanced between Tory and Labour in 2008, tilted towards Tory in 2014 (14 plus 1 DUP, as against 6 Labour). There were four daughters in 2008, just 2 in 2014.
And there's no sign of the pattern changing, with Blair, Kinnock and Straw junior all said to be seeking parliamentary seats -- and there's no doubt more. And the USA, of course, have the families Bush and Clinton.