Rollo the dog belonged to Henry Walker, manager of the Philadelphia Steel Works. He survived the 1864 Sheffield Flood, and was given a presentation dog collar with his name inscribed on it, "owing to his narrow escape from drowning".

Rollo is sometimes credited with rescuing a baby in a cradle from the floodwaters. This is depicted in a painting called "A Faithful Friend" by A Sosell, which was used for advertising tea. John Everett Millais’ "The Flood" shows a similar scene of a baby floating safely in a cradle with a cat, but no dog. A small version of this is printed on a canvas cigarette card on display with the dog collar in Weston Park Museum. Millais’ painting is based on newspaper reports of a child in a cradle being washed out of a house by the flood waters, but the dog as rescuer seems to have been an embellishment of the story.