I've never personally dealt with such grandmothers... They belong in a mental hospital. And for the injured boy, they could have given a suspended sentence. Fining them is pointless, of course. Although, I'm not sure if some of the penalties apply to pensioners? Can a 70-year-old grandmother really be sent to a women's prison?
Bow down and hear our cry,
Our earthly rulers falter,
Our people drift and die,
The walls of gold entomb us,
The swords of scorn divide,
Take not thy thunder from us,
Take away our pride.
G.K. Chesterton: English Hymnal