Jack and Sean – not their real names – suffered severe abuse from their father for more than 15 years.
They were regularly locked in a cellar, and beaten but the authorities took years to intervene.
Wednesday marks the first day they will be able to seek compensation, after the government reversed a rule that stopped victims of violent crimes before 1979 receiving compensation if they had lived with their attacker at the time of the incident.
Lewisham Council said “since the 1970s and 1980s, measures to protect children from child abuse have improved greatly”.
Watch the Victoria Derbyshire programme on BBC Two and BBC News channel, 10:00 to 11:00 BST – and see more of our stories here.