@tapeworm Nope, the 2nd couple are not siblings of my daughter and son-in-law. I do have another younger daughter that runs, but she did not do the Peoria Marathon. My daughter, son-in-law, and the other couple all live in and belong to a running club in Springfield.
In November, the son-in-law is running a marathon (he's done a few), older daughter (his wife), running a half-marathon, as is my younger daughter; and wife and I are walking a 5k. (Third year in a row for us). This all takes place in Indianapolis, in an event called the Monumental Marathon.