How Many Children Simulation

A newly married couple agrees that they want to have children. The husband wants to have at least one son, and the wife wants to have at least one daughter. They are interested in finding how many children they can expect to have before having one boy and one girl. Each dot in the dot plot below represents the number of children in one trial of "having-children-until-both-genders-are-represented." There are 100 trials.