As indicated in the credits of last week's episode, the Egyptian hippo deity is Taweret, the goddess of 'women and children who helps souls pass into the afterlife.
Taweret (in her upbeat way) is there to instruct Marc and Steven to balance the scales of their hearts, so they can be judged for the afterlife.
However, when a child shows up in the room, Steven loses his composure and splits from Marc, running into a different memory: the death of Marc's little brother