We never said specifically, but I assume Lucy was around/near the same age as Ben in each episode.
(sorry for the lateness of this reply)

But on "Ready to Rumble", it was a standalone story so they never sent me other scripts/outlines to read. If there had been something that needed to track over multiple episodes, I would've relied on the head writers Klein/Pugsley to give me any info I would need.

Hope this helps!

Thanks for the kind words. As for your question, on Ben 10 I didn't have access to the other episodes (except "Big Fat Alien Wedding" because I wrote that one). On some shows I've worked on, I'm given the other scripts/outlines so I can help connect my story to the other ones.

HEAT. And of course MAJOR LEAGUE. All respect to Jobu...

We never said. When I wrote it, I assumed it took place on another planet, but that's not official or anything.

When I wrote them, I assumed that their mom was an alien, but that's just my speculation. I don't think it was ever said officially one way or the other.

I don't think his origin was ever officially established, so Derrick and Duncan are likely correct.

Sorry. Good question, but I have no idea.