Try as I might, I cannot recall having ever seen this before.
At Thunder Valley Raceway on August 23, SERRA was honored by having three generations of the same family racing slot cars in our retro series.

The picture shows Steve Harrrington, the clan's patriarch, on the left, his son Chad Harrington in the middle, and on the right is Alex Harrington, Chad's son and Steve's grandson.
Doesn't really surprise us that the Harrington family would put on this tri-fecta, as Shirley and Steve Harrington own Raceworld Speedway in LaGrange, GA, a regular stop on the SERRA retro tour.
Still, we believe this to be a fairly rare occurrence in 1/24 slot racing. Anyone else know of three generations of the same family involved in slots at the same event?