Louis's beloved cat, Peter, dies from old age. This is shown through a single shot where Louis is distraught to discover Peter's motionless body on the floor. The body is facing away from the audience so the cat's face is not visible, and there are no visible signs of injury or illness.
When he has flashbacks to a nightmare he had as a child of a sinking boat he thinks he can’t breath. He can. But he’s very distressed in the night terror and thinks it’s real.
Sort of? A shipment of hand-made cat figurines is lost when the ship carrying the goods is hit by German missiles circa World War 1. However, this was merchandise to be sold, and as such it never belonged to a child.