[They had this argument before, but this is probably a good time for total honesty.] ...Well, I got no choice but to lie back then. You'd have wanted nothing to do with me if I told the truth. [That, or sold him out because life in Gray Terminal works like that. Nobody likes dealing with nobles there, unless there's cash to be had.

And then, Sabo's eyes widens. That's no small honor Ace is offering him, and he's very much aware of it.] W-what... I can't do that! I'm not part of Whitebeard's crew. [Not part of his family.]