UK mother Kate Dagley, 45 and her daughter Karen Jenkins, 27 were kept as prisoners by Jean Kelly, 53, her husband Michael, 43, her daughter Anastasia Hitt, her partner Ian Healy, 29 and their baby.
Ms. Dagley and Miss. Jenkins were living on the same floor in the apartment block in Coventry when they became the family's victims.
The court was told Jean Kelly, who despite being confined to a wheelchair, was the ringleader and nicknamed her baseball bat "Bob." Kelly was found guilty of two charges under the Modern Slavery Act.
Prosecutor Graham Russell said: "This case concerns the systematic and brutal assault and detention of two women."
"Jean Kelly, we say, is the guiding word in the detention and forced labour of both of them," prosecutor Graham Russell told the jury.
The court heard the couple used fists and baseball bats to beat the mother and daughter.
READ MORE: Your Backyard or Mine? Britain's Modern Slavery Getting Closer to Home
'Booted & Punched'
The two women's ordeals ended following and anonymous tip-off to police who discovered the daughter with extensive facial injuries a fractured breastbone and broken finger. Her mother was found with two fractures to her back, two broken ribs and bruises all over her face.
Karen Jenkins told the jury at Warwick Crown Court, "I don't remember how many I had. I was constantly getting booted and punched, booted and punched."
The court heard Miss Jenkins was kept as a slave for three weeks where she was forced to carry out domestic tasks for Anastasia Hitt, her partner Ian Healy, 29 and their baby.
"Her free will was comprehensively extinguished. She was serving Anastasia Hitt under coercion," Mr. Russell said.
Without realising, defendant Anastasia Hitt provided the strongest evidence against herself because she kept an app on her smartphone which recorded all conversations.
The jury was told one recorded included a discussion about Miss Jenkins being 'locked in'. Hitt complained about her speaking to a social worker through the letterbox.
The defendants will be sentenced next month.
READ MORE: Family 'Devastated' After Man Lived & Died as Modern Slave in London