Dean's confusion matched her own, just before she mentioned that Red was Kat's mother. Ever since his accident as a young child, he didn't remember his blood relatives, then again, they were more 'High Class.'
He honestly did not know that Kat and Shannon were related, though if he had dwelled on it, their scents were similar. His expression grew even more bright as he swiftly moved forward and wrapped his arms around Kat, lifting her up as he did with everyone else he gave a hug to. Though, as he was with everyone else, he was still very gentle! After less than a moment, he put her down, and let go, taking a step away.. He realized that he got too excited.
"Dean is sorry... It is just, Dean does not have very many... Friends, and to know now that Kat is Red's.. Child.." He took another step away, his snout turning from that friendly smile into a deep frown. "Dean got... Uh... Dean was just happy to know that. Dean is sorry.." He twiddled this thumbs in an embarrassed fashion, as he stared at the ground.