As Melania and Barron Trump moved into the White House this past weekend, Barron became the first son of a president to live in the residence since John Kennedy Jr. played under his dad’s desk in the early 60s. For over half a century, the White House residence has been the domain of daughters; nine of them to be exact. The sons of presidents, including future president George W. Bush, have all been too old to live with their parents. It’s a statistically unlikely streak.
Currently, in the United States, the odds of having a boy are slightly better than having a girl: around 51 percent. There’s a tricky explanation for why this is the case. That’s because, at conception, the ratio of male to female embryos is pretty much even. So what’s happening? A 2015 study found that more female fetuses are lost during pregnancy, bumping the male birth rate a tad higher. Things get even more interesting considering that individuals who’ve traditionally run for the office are powerful men. According to the Trivers-Willard hypothesis, evolution should allow more boys to be born to men and women who have the resources to ensure that they will thrive and propagate the family genes. That’s a controversial thesis, to be sure, but one that has seen minor consistent support since it was first proposed in 1972.
So given a higher birth rate for males and the possibility that more males will be born to men and women of high status, it would be safe to assume that there would be more Barrons and Johns in the White House than Chelseas and Jennas. But, even If you look at the current living children of recent presidents, the higher male ratio does not play out.
There are 16 female and 15 male presidential progeny currently living. The oldest is 73-year-old Lynda Bird Johnson. The youngest is 11-year-old Barron. Those stats look about right, but don’t think that politicians don’t consider the optics of childhood. During the 2008 election, a leaked email from a Clinton adviser pointed towards the run of young daughters in the residence, describing it as “another historical trend working against Mitt Romney and his brood of sons.” The email read noted that, in the last 80 years, a president without a daughter has been elected precisely once.
There could be a couple things at play here. It turns out that there’s some research suggesting that people in positions of high stress are more likely to have daughters. Politics is clearly a high-stress game. Moreover, older men and women are also more likely to sire daughters. Most presidents are well beyond their 40s by the time they reach office. And that’s another factor working against having first sons in the White House.
There’s also a possibility that voters have become used to the idea of a first daughter for cultural reasons. Or maybe the country is still being haunted by the last brothers to lived in the White House—the sons of Roosevelt, who nearly tore the place down with their antics.