Colouring-in books and pattern books are a boon. It doesn't take much imagination or effort to get a child interested in trees, flowers, birds and wildlife, in searching out the influence of horses on the design of canal structures, in knots and other sailorly pursuits, and a host of other activities. Small caged birds and mammals seem to quite enjoy the extra amount of fresh air that they get on a boating holiday. Cats seem to settle in quite quickly. Owners whose pets use an indoor cat litter tray take it with them, so that the cat will recognise it for what it is.
Cats seem to be able to take a meander ashore, and pick out the right boat to return to.
You either need a well trained dog, or a lead, preferably both. There is a great temptation to take on a boat, and many boaters do. But, there can be problems. The obvious answer is 'On the roof'. There are many places on the system where there is more than adequate headroom to carry a bike, but there are also many places where a bike on the roof can get caught.