Grandparents

A grandparent is a human that has produced one thousand offspring, (hence the origin of the word). On achieving this feat, the new grandparent shouts 'full house!', and is then officially designated with the title and given some comfortable shoes by Her Majesty the Queen.

Grandparents can be found in armchairs, at bus stops and in deckchairs in UK seaside resorts. Indeed, they are so common these days that they can easily be acquired; you may even have one yourself.
Your grandparent should be refuelled regularly with Werther's Originals and tea (some high-performance models also take sherry).
It can be useful to cover your grandparent with a tartan blanket. This will calm him or her down, and discourage attempts to escape.