All the houses that appear in the film are very close to each other in the same Buenos Aires neighborhood, Versalles. The main house (Elvira and Sergio's) became too old with the years. It was about to face demolition but the city's government decided to mark it as a cultural landmark and it was totally repaired. Now, it is a site of pilgrimage for thousands of fans who visit it all year round to take pictures and tour around the neighborhood. The house is inhabited by the same family who owned it at the time of the filming. They even have a female dog as pet named after one of the characters in the movie: "Matilde" (the young daughter of Elvira and Sergio).
You can hear the voice of Antonio Gasalla (who plays the role of Mama Cora) yelling to Mama Cora in the scene where she is watering the plants on the roof terrace and accidentally drops the teakettle on the street.
At the funeral scene, Elvira receives a bunch of flowers with a band that reads 'From Dora and Alfonsina'. Elvira immediately takes off the final 'A' of Alfonsina's name so the flowers would have been sent by 'Dora and Alfonsin'. 'Raul Alfonsin' was the president of Argentina at that time.
The film is full of famous tag lines which still nowadays are part of the Argentine everyday talk. Some of those lines (like the one shout by Elvira: 'the parrot shit on me') were totally unscripted and added by the actors as a joke. Director Alejandro Doria found them so funny that he decided to keep them in the final movie.
The complete name of the character of Mama Cora -which her sons find so difficult to remember- is: Ana María de los Dolores Buscarolli de Musicardi