Thanks to smrtmnky for this, originally from NPR's Scott Simon. Scott had said:
Smallest member if [sic] our family atop seriously cute pony (Cheerio) at Mark West stables:
THE MINI PONY'S NAME IS CHEERIO. I looooved Cheerios growing up. You can have your sugar cereals that are good every now and then, but Cheerios are always where it's at.
I quite honestly have no idea how or why a baby sock monkey or something is a part of Simon's family, but I'm cool with anything else small riding great small horses.