Zuko easily accepted Sokka's hug. From the point that he'd come back from, he and Sokka had been through a lot together, and he owed the guy quite a bit. But something caught his eye that made him pause.

Sokka's sword. He had lost that in battle. Katara's reaction going unnoticed for the moment as he focused on that.

"When did you guys get here?" This question having more than one meaning.