Wow, that certainly seems petty. I mean don't get me wrong, I understand copyrights and their purpose, but, this just seems ridiculous. She never claimed she created the characters, and, I don't see it as being a threat to Dr. Who.
It just kills me when big companies go after the "little" people...Like the RIAA going after kids downloading music while they totally ignored the complaint I submitted when I worked at a cd store...The company I worked for was burning cd's and SELLING them to people as if they were original copies! My old manager was the one doing it and all the money went right into the companies pocket! Oh, the RIAA listened to me, but, they never did a thing about it, it just got swept under the carpet.
Maybe if this woman was making a business of doing this, that would be one thing, but, to go after a fan who did this for enjoyment is a completely different thing.