Alpha Lorenzo Walker – a cousin of Wonder - and his girlfriend Tamara Eileen Diaz were accused of demanding money from Wonder in order to not release a tape that allegedly showed squalor at the home of the singer's late mother.
The couple initially demanded $5 million to not release the footage, but were ultimately arrested after Wonder and his lawyer alerted police.
An LA district attorney spokesperson has now confirmed that Walker was sentenced to 292 days behind bars for pleading no contest to extortion and has been released on time served, reports The LA Times.
Walker will also be required to attend 78 Narcotics Anonymous and mental health classes during his three-year probation.
Diaz was also released for time served on her jail sentence.
Wonder has not commented on the verdict.
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Watch Stevie Wonder perform 'As' below: