What is everyone's middle name in the pjo series?

Now that あなた mensoned it, I havent really thought about it. i read somewhere that it's
Percy Allen Jackson
Annabeth is probably Annabeth (i don't know her dad's name) Chase
Grover (no idea, timothy?! :D, like brandon. t. jackson ;)) Underwood
Ok this is realy hard i give up, i'm sorry, i tried surching in google, but the only thing i found was 質問 about what their middle names are. I think that only RR knows their middle names.(but probably he hasn't thought about it either.

The answer to this 質問 is unknown. Only Rick Riordan knows this. but good question!

Aren't the middle names... like from the other parent? so like, since the gods don't have a middle name, neither do the demigods....?

I'm not really sure...

Rick never mentioned it so i guess they don't have one. Not everyone has one あなた know.

This 質問 was answered a few months 前 via twitter. Nobody really has middle names, really, except Rachel Elizabeth Dare