When I saw this photo of Darby,
the words "keep on truckin'" popped into my head.
How many of you are old enough to remember the "keep on truckin'" craze?
The saying meant something along the lines of "stay with it; you're doing a good job."
Although the saying has it's roots in the 1920-1930 jazz scene, it really took off in the late 1960's when Robert Crumb created a one page comic with the title "Keep on Truckin.'" I'd ignore copyright laws and copy the image here, but if Wikipedia is to believed, poor Mr. Crumb and his copyright have been violated enough, so I'll just send you to look here.
In addition to all those t-shirts, mugs and posters bearing the image and the saying, there was a TV show by the name. The show aired in 1975 and had an astonishingly short run -- 4 episodes -- if this write-up is to be believed. Sounds like the best thing about the show is that Rod Serling was supposed to introduce each show, but died two weeks before the debut. It sounds like he was lucky.
Born in 1943, it looks like Robert Crumb is, ahem, keepin' on truckin'.
Shortly after I took the photo, Darby stopped truckin' and took a nap in the shade.