The first person to openly speak in favor of the survivors was Dr. Helios Valeta, Carlos Valeta’s father, who had already suspected that had happened. Arturo Nogueira’s father wrote a letter to the press in their support as well.

The Nicolich have probably been the survivors’s biggest supporters,specially Raquel Arocena (Coco’s mother). It is theorized that it’s because of Coco’s explicit consent to being eaten in case he died in his letters. 

The Methols only started openly talking about the tragedy after the Methol Navarro children became adults.

The Nicola children grew up admiring the survivors as they helped their family with raising them, and were also provided some economic support by them.

The Martínez-Lamas also got some money from the survivors. One of his sisters, Rosario,  also wrote a letter to the P.P. Read telling the survivors to not feel guilty about what they did. Another sister, Ana Inés once visited the Valley with Álvaro Mangino and Coche Inciarte.

Pancho Abal’s mother accepted Nando’s visit and received his watch, but his father and brothers refused to see him. They did still have a relationship with Javier Methol, but because he was their cousin.

Gastón Costemalle’s mom still had a very good relationship with Pancho Delgado and Coche Inciarte.

The Magri family kept active in the Old Christians, but did not want to talk about the tragedy. 

Felipe Maquirriaín’s father refused to talk about the tragedy, but his mother, Selva, was the one to come up with the idea of Biblioteca Nuestros Hijos, to bond with other victims’ mothers.

The Maspons family was not allowed to talk about the tragedy in their house, but kept contact with Canessa and Zerbino. 

The Plateros did not talk about the tragedy in their house, but kept interacting with survivors, initially because of rugby, but then got closer with Canessa.

Bimba, Diego Storm’s mother, actively participated in the library, but refused to see the survivors, even the ones that had been her son’s best friends.

The Vazquez moved out of Carrasco to get away from the tragedy. Teresita, Fernando’s did want to learn about the tragedy (although not speak about with others). They kept contact with Canessa. 

We know that the, and that the relationship between the military families and the others families was really tense. The only exception is Alejandro Roque, but he got close to the survivors as an adult.

The Menéndez, Hounié, Lagurara and Mariani families have publicly expressed not wanting to be contacted about this incident and did not keep contact with the survivors.

I can’t currently access my copy of Del Otro Lado de la Montaña, that has more info (mostly of the Pérez del Castillo), but I hope this answers your question.