I can think of a few things my mother did right. One was to nag me into taking an interest in things besides cartoons. This has kept me curious, broadened my horizons, and has even helped my art! I meet so many cartoonists who haven't grown aesthetically since age 14. They are sad and boring.
The retouching book is, of course, way out of date, but has good graphics. Anyway, it was a buck.