Sophia is resistant to getting a hearing aid. But early in the series, when she comes to live at the house, she says that she can hear a bird break wind in Lauderdale when she turns her hearing aid up to 9.
For the sake of a joke ("Your initials spell bed!?") it is revealed here that Blanche's middle name is Elizabeth. However, in the episode Wham, Bam, Thank You, Mammy (1990), when the character of Mammy Watkins calls Blanche by her full name, her middle name is Marie.
Dorothy mentions that she and her mother are going to see the philharmonic perform "Beethoven's Sonata No. 29". Sonatas are musical works for piano solo. A philharmonic orchestra would not play a sonata.
Rose tells Dorothy "I can't believe that I made that crack about the nautical toilet (to Blanche)" but Dorothy said it not her.