He also has an interesting view on which attribute predicts a good football future.
The San Francisco 49ers head coach was asked on Monday about President Obama's remarks that he would "have to think long and hard" before he let his non-existent son play football. Well, Jim Harbaugh has three real sons of his own and he didn't hesitate in seeing the advantage the president's cautious stance gives the youngest son of his second marriage.
Also benefiting little Jack Harbaugh, who was born in September at the start of this football season? The prodigious size of his big noggin.
Here's what Harbaugh told the assembled media in New Orleans on Monday:
"Well, I have a 4-month-old, soon-to-be-5-month-old son, Jack Harbaugh. If President Obama feels that way, then there will be a little less competition for Jack Harbaugh for when he gets old enough. That's the first thing that jumps in my mind if other parents are thinking that way.
"It's still early. Jack, like I said, is only five months old. But he's a really big kid. He's got an enormous head ... As soon as he grows into that head, he's going to be something. It's early, but expectations are high for young Jack."
We haven't seen any pictures of Jack Harbaugh, so we'll have to take dad's word that his son's cranium is like Sputnik (spherical, but quite pointy at parts). It's interesting, though, to see that Harbaugh thinks a huge head portends gridiron success because usually people believe big hands or feet will translate to athletic success.
If young Jack Harbaugh does fulfill his father's expectations and get into football, he'd be following in the footsteps of his half-brother Jay, who is the eldest son from Jim Harbaugh's first marriage. Jay is a Baltimore Ravens assistant under his uncle John Harbaugh and previously worked as a student assistant at Oregon State while his father coached Stanford.
Also interesting: Jack Harbaugh was born on Sept. 4, 2012, which Jim Harbaugh helpfully points out is the fourth day of the ninth month — a great day to be a 49ers fan. Jack shares that birthday with his half-brother James, who was born on Sept. 4, 2006.
h/t: CSN Bay Area