There is a soft snort of amusement, because it's really pleasing to see two people who are so familiar and comfortable with each other. It reminds Kaldur of Tula and Garth--which shouldn't hurt as much as it still does, but at least it is much less than he remembers it to have been--of home. It is comforting in its bittersweet nostalgia so he watches, choosing to enjoy it.