The old man confronted the two brothers after one of their family members filmed his grandson with a mobile phone, regional online daily Las Provincias reported on Thursday.
What was filmed by the brothers’ relative remains unclear.
The heated argument soon turned violent when the vicious siblings, both with criminal records, grabbed hold of a stick and an axe and began hitting the old man on the head.
The victim’s daughter and husband were unable to stop the attack and were also punched, axed and stoned by the aggressors.
A witness at the scene told the online daily, “The attack was brutal”.
As soon as they were able to escape, the injured family called an ambulance and the police to explain what had happened.
Emergency services, who initially feared for the old man’s life due to the deep cuts he’d sustained to the skull, told Las Provincias his condition was improving.
A judge in Lliria (Valencia) sentenced the brothers to prison for attempted homicide, court sources reported.
Police in Pedralba had known of the tension between the two families, who only live 50 metres from each other for some time.