At the beginning of Season 7 Markie Post discovered she was pregnant so they wrote Christine's marriage and pregnancy into the storyline so that she could continue to appear. She gave birth to her actual daughter, Daisy, on March 30th 1990, shortly after the season wrapped.
Final appearance of John Astin as Buddy, Harry's dad.
During the series they claimed several times to be on the 18th floor. The elevator's floor indicator where Christine had her baby shows the highest floor to be 12.