The reason why Pearl Forrester sometimes calls
Crow "
Art" is a reference is a piece of
viewer mail that was shown on the show several years before Pearl was introduced. A child's drawing of
Crow labeled the golden robot as "
Arthur", and the
writers latched on to this, finding it hilarious. As such they began having Pearl call
Crow "
Art".
Also, for the record Pearl first appeared in the Season 6 episode "Bloodlust" when she came to visit Deep 13. Dr. F was quite annoyed that his mother and TV's Frank had a long friendship in which they had been sending letters to each other for years. In fact, during this visit Pearl and Frank spent more time together than she and Dr. F did.
Pearl has also had a number of husbands over the years, all of which died horrible yet unexplanable deaths during the Honeymoons.