David Rooke admitted false imprisonment and ABH, his son Jamie, 19, to ABH and affray and Donna Rooke to battery.
32 year-old Craig Kinsella was kept in the family's garage and made to scavenge for food from bins.
Craig, who has learning difficulties, was made to work from 7:30 am until midnight and beaten with pick axe handles.
More top news
Longest cold spell of winter so far. Bitterly cold with further wintry showers, significant snowfall likely over hills
Demonstrators will gather in Lincoln this morning to protest against proposed cuts to the city's local fire service.
Jon Mitchell with tonight's weather