Reader's Digest cartoon: The family way

I find my best cartoons are the ones inspired by real-life events. I recently met a married couple who had a young child plus a boy and a girl who were from each of their previous marriages. I was finding it hard to remember which kid was the offspring of which parent when it occurred to me ... what if the parents couldn't keep track? Hey, cartoon idea! This gag is in the August issue of Reader's Digest. By the way, no comment is intended on what the media has taken to calling "blended" families. It's just a joke.