In Money Well Spent, on this site, Chapter 3, it says, "Surprisingly there were a lot of vets at the station, and they all rallied behind us. We even did a PSA together showing us in uniform ..."
What is a PSA?
The "vets" in the story are veterans, not veterinarians. Other characters are TV reporters, TV cameramen, with references to websites and YouTube.
I tried to look up PSA on the Internet, but the only reference I found was to a blood test for prostate, which makes little sense in this context. I found nothing referring to veterans or the military, or TV reporters, cameramen or websites or YouTube.