This led to me to look for more and, as I said above, this theme was used time and time again in almost every comic you can name. Here's yet another example, a Billy Whizz strip from 1968 (although this is actually "what if Billy was alive in..." and not a family tree, but it still works).
And finally, here's Benny Bones' family tree, in which it is Benny's teacher is doing the talking.
There are many, many more of course and I haven't the room or time to scan them all, but I'm sure if you browse through a few comics it won't take you long to find another example of one of the most overused ideas in comics!
And of course, there's also the literal Family Trees, which I covered here: