More Dutch van der Linde Headcanons: Sillier, Shorter, and Less Researched Ones Edition (sfw)
Restless Legs Syndrome. One of the causes of his insomnia.
Does not believe in the soul, agnostic/deist, the way of Jefferson.
Tries to avoid tanning when he can; even if he won't admit it, he buys into the time's mainstream beauty standards.
He has a lot of microsleeps and short naps in the saddle due to his insomnia. Tries to hide/compensate for this as much as possible.
Pennsylvania at the time of Dutch's birth and childhood had many pacifist Anabaptists, particularly in the region he likely lived in at the time, as his father was from the Netherlands. There was a lot of stigma faced by his father as a soldier, and his mother as a war widow, because of this.
The beauty mark on his cheek was inherited from his father. His mother would look at him and see his father, projecting her grief onto him. One of the reasons he left.
His curls were inherited from his mother, who cut his hair short and tried to smooth it down to make him look more like his father.
The little patch of hair under his lower lip, uncommon at the time, hides a scar he received some time after running away from home.
He was never baptised, save one time he ran half-clothed into a river to hide from the law among penitents.
Bad joints and back that he takes every effort to hide, to never show weakness. He rubs his joints at night when he thinks no one can see.
He has an estranged sister, a few years younger, and cousins he grew up with. (His uncle is mentioned but not named in canon.)
He fed stray dogs as a child.