What? You didn't expect him to sit around and let his sister soak up all the sympathy herself, did you?
The injury you see is the result of a post shower tizzy last night when Hank couldn't believe that his mom had the gall to tear him away from TV to take a much needed two-days-post-camp bath. He stomped, on wet feet, out of the fastest shower he's ever taken only to land flat on his bum, smacking his brow bone on the wall on the way down. As a bonus to the head injury, two camp ticks were discovered burrowed in each shoulder.