[Espy]

Well, it'd depend on who's yelling at him. His mom would probably use "Lucas"; his dad would probably say "Lucifer", and Gabe would just look at him with puppy eyes and whisper "Luuuuuke? Can you get me a cookie?"

They ARE cognates.

Kevlar and priest robes seem to be a strange combo, no...? And hm, vow of silence. This might be interesting, if it does happen. (I've a character who's actually mute, and it's great practice having to figure out how to make him express himself.)