Ben Fogle and Kate Humble spend Christmas with the animals. Two Siberian tiger cubs take their first steps into the park - and have their first encounter with cars. Elsewhere, the staff at the house face their biggest challenge of the year - finding a tree on the estate that is just the right size for the stately home, chop it down, and get it inside without causing any damage. Plus, Jean Johansson mucks in with the keepers to hand out Christmas treats to their much-loved creatures