This looks like a family picture in which Kaladin was around being a body guard during the whole thing, and Dalinar was like "Stormblessed, get over here." And they made him come in for the picture. And he only half smiled because Dalinar gave him a look. Because Dalinar is low-key trying to take Kaladin under his wing and Kaladin is being the moody teenager like "you aren't my real dad!" I don't know sometimes I see it this way.