A what from whose what?

There are a lot of questions that I didn't ask of my parents and, probably, an equal number of answers to which I did not pay attention.

I found this in a box of papers that we'd collected from my father's house. The box included my grandparents' citizenship papers, birth and marriage certificates, and passports.

The receipt is for the cost of administering ether as an anesthetic while my uncle was having a bullet removed from his arm.