Using the keyboard for control, press the [Z], [X], [C], and [V] keys (alternately, [A], [S], [D] and [F] may be used instead) at the appropriate time to get all family members to safety. Adding to the difficulty of this not-so-simple game is the fact that the keys control different functions, such as jumping, swatting, and starting and stopping. It's enough to thoroughly wrap your brain into knots.
Not a long game, nor a complicated one to understand, and yet oh-so-hard to do correctly. Give it a try and see if you can manage a reward greater than toilet paper.