Tree diagrams can be used for any situation involving a sequence of events. Each possible sequence of events is represented by a path through the tree diagram. Branches are labelled with the probability for the branching conditional on the branches to the left.

For example, if a family want at least two children and no more than four, but will stop when they get a boy, the possible sequences of events are:

The joint probability for any sequence of events is again found by multiplying the probabilities on all branches of the tree corresponding to this sequence. If the probability of each child being a boy is \(\frac 1 2\), then the probabilities for the possible sequences of boys and girls are as shown in the diagram.