Glenn and Jerusha want to have another child, but they need to find a surrogate. Cheyenne mistaken agrees to do it and tries to back out, but her boyfriend is supportive of the decision after learning that they’ll earn $20,000. He decides to spend that money (which he calls infinite money) on a new hot tub. The increase in their income results in an increase in their demand for normal goods. In this case, the hot tub is likely income-elastic.