When Hidden Hills' beloved gardener, Juan, unexpectedly dies, the aliens are forced to deal with something totally foreign to them. Debbie and Marty struggle to explain that death is something that comes to all humans, eventually, but Larry Bird is determined to find a way to solve that little problem, starting with the recently departed Juan.

When the entire Weaver family gets sick, it forces the Bird-Kersees to confront something new and terrifying -- the common cold. The Bird-Kersees - especially Larry - can't understand why Debbie takes care of her family even though she is exposing herself to their cold. Having learned there is no cure for colds, Larry makes the community quarantine the Weaver house, but Reggie has other plans.