Assuming boys and girls are equally likely, find the probability of a couple having a baby boy when their fifth child is born, given that the first four children were all boys. The probability is \( \square \). (Type an integer or a simplified fraction.)

The probability of having a boy or a girl for each child is independent of previous births. Since boys and girls are equally likely, the probability remains the same for each birth regardless of the outcomes of the previous children. Therefore, the probability that the fifth child is a boy is: \[ \frac{1}{2} \] **Answer:** \(\frac{1}{2}\)