In this episode, which aired in February 1991, the Huxtables are celebrating their 27th anniversary. This means that they were married in 1964. In the episode, It Comes and Goes, Clair refers to a Memorial Day weekend in 1967 when Sondra was three years old. This means that Sondra was born before May of 1964. If Cliff and Clair were married in February, 1964, then that means that either Sondra was born before they were married or Clair was pregnant with her when they got married!!!!
This episode is supposed to have Cliff and Clair celebrating their 27th anniversary. Why did they skip over the 25th? They had big celebrations for Russell and Anna's 49th & 50th anniversaries, so why not the 25th? Silver anniversaries are usually big occasions to most people.
During the course of the episode, Cliff starts to get sick, running a fever. If Cliff were really as sick as he was, how could he taste the soup? Most people struggling with a cold can't smell or taste anything because their sinuses are clogged.