I'm sorry if this is outside of the norm for what is
entertained at HN, but I mean this in the most earnest sense. To merely explain this away with a wave and a hand and a sound of "coincidence" is wrong. It suggests at least something else. May we speculate for the sake of contemplation without ridicule?
Here are the facts:
Abraham Lincoln was elected to congress in 1846.
John F. Kennedy was elected to congress in 1946.
Abraham Lincoln was elected President in 1860.
John F. Kennedy was elected President in 1960.
Both Presidents were shot on a Friday.
Both Presidents were shot in the head.
Both were assassinated by Southerners.
Both were succeeded by Southerners named Johnson.
Andrew Johnson who succeeded Lincoln was born in 1808.
Lyndon Johnson who succeeded Kennedy was born in 1908.
John Booth who assassinated Lincoln was born in 1839.
Lee Oswald who "assassinated" JFK was born in 1939.
Lincoln was shot at the Theatre named Ford.
Kennedy was shot in a car called Lincoln made by Ford.
Lincolns assassin ran and hid in the Theatre warehouse.
Kennedy was shot from a warehouse and his assassin ran and hid in a Theatre.
Both Booth and Oswald were assassinated before their trials.
But it's pure post-hoc construction... something akin to creating "just so stories" just with the elements drawn from an assemblage of factual events[1]. There's no particular reason to think that there was any kind of causal connection or other deeper relationship between these events.
[1]: note that in the case of this Lincoln / Kennedy thing, in the forms you usually see this distributed in, it appears to not be the case that all of the individual assertion are true.
See also:
https://en.wikipedia.org/wiki/Lincoln%E2%80%93Kennedy_coinci...
https://en.wikipedia.org/wiki/Data_dredging