The Days and Nights of Sophia Petrillo - S4-E2
Continuity mistake: Dorothy mentions that her Grandma, the mother of Sophia, died at 94 when Dorothy was 6. However, in the season 3 finale, there was an entire scene showing Sophia's mother visiting Sophia and Salvadore on Mother's Day, accompanied by young but certainly adult Dorothy.
Answer: Ice makers were a new invention, advertisement purposes.