tip: "sherlock (tv)" m/m NOT "sherlock holmes/john watson"
Nice touch naming Luffy as Whitebeard's youngest son because we allllll know he was!
I think they were referring to Ace with that line. Author mentioned "his sons, to his son’s brother" earlier, so Ace is most likely his youngest, while Marco is the oldest.
I was indeed :) Luffy's more like... i don't know, the crazy nephew? One you don't see for months and suddenly he's standing on your doorstep with the biggest shit-eating grin ever and you're kind of dreading what he's going to say but also he always gets into the weirdest shit and you can't wait to hear what happened this time xD