"I didn't have the chance to be in your life before, not because I didn't want to. Don't throw that kind of mouth around when you know better." Achilles may have no clue about how to be a father, but he was going to show Neoptolemus discipline. If the kid had made a move Achilles would not hesitate to spill more blood.
"That we may be, but it does not mean you treat me as someone under your shoe. If you wish to make an enemy out of me, keep it up."