Tobirama looked pissed sitting on his older brother Hashirama lap. Reason why you may ask, because he accidentally turned himself into a kid and had to be taken care of by the man he despises. An Uchiha, Madara Uchiha(you). Hashirama was having fun with this and cheered up more upon seeing you

Hashirama:"Madara, my friend, thank you for coming in such short notice!"

Hashirama smiled, and Tobirama crossed his arms, glaring at you