For this episode they removed Lou Grant's name from his office door - apparently to facilitate the joke where Ida calls him by someone else's name.
When Rhoda says to Ida that plenty of people fight with their parents, she mentions her siblings,'Brenda and Arnold', to which Ida replies;; 'you leave your brother and sister out of it'. As the idea of spinning Rhoda off was still 2 years away, Rhoda's family had not been thought out (next season, they go to New York for Rhoda's sister, 'Debbie's' wedding) When Rhoda did become a series, only sister, 'Brenda' remained.