Shakeela Naz and her son Shazad Ali were found guilty at Nottingham Crown Court on Tuesday of the murder of 19-year-old Rukhsana.
The court heard the pair believed Rukhsana Naz had brought shame on the family by having an extra-marital affair and becoming pregnant.
'Horrific offence'
Her younger brother, Iftikar, was cleared of murder.
The judge, Mr Justice Tucker, said: "The jury have convicted you both of murder.
"It was a particularly horrific offence, involving as it did the death of a young pregnant woman, who was already the mother of two children, at the hands of her own family."
Rukhsana had married at the age of 16 to a man in Pakistan.
She was strangled to death with an electric flex by her brother at their family home in Derby last March after becoming pregnant by her lover.
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Man 'confessed to murdering sister'
(26 May 99 | UK)
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