Is this a joke or something else?
Duh?
No its not a joke. George Washington conducted a mass vaccination of his troops. The cut your arm and then placed a piece of thread with small pox puss in the cut. You got a milder case of small pox. Then later they realized you could use cow pox virus so they scraped a place on your arm raw and rubbed some cow pox puss in the scrape. You got cow pox which was mild but were then immune to small pox.
No joke, but my mistake, it was his oldest son Franky who died of it at age four in 1736 not a daughter.
Actually he lost his son:
When smallpox came to Philadelphia in 1736, infecting and eventually killing his son, Ben Franklin appeared to have a change of heart about smallpox inoculation when he wrote in his autobiography,
“In 1736 I lost one of my sons, a fine boy of four years old, by the smallpox taken in the common way. I long regretted bitterly and still regret that I had not given it to him by inoculation. This I mention for the sake of the parents who omit that operation, on the supposition that they should never forgive themselves if a child died under it; my example showing that the regret may be the same either way, and that, therefore, the safer should be chosen.”