Tanya Tracey, 31, of Flowerhill Way, Istead Rise, failed to notify Gravesham council that her landlord was also the father of her 16-month-old baby and continued to claim housing and council tax benefit.
It meant she defrauded them out of £3,583.
The law states that people are not eligible to claim housing benefit if the parent of their child is their landlord.
Tracey admitted dishonestly failing to notify a change of circumstances at Dartford Magistrates’ Court on Monday.
She was fined £100 and ordered to pay £250 in costs and a £20 victim surcharge.
The council has already starting reclaiming the money it is owed.
The court heard one of the factors leading to her prosecution was her relationship status on her Facebook page, which stated she was “in a relationship”, alerting the authorities to a possible discrepancy.
Mandeep Sahota, defending, explained that her client had found it hard to deal with the strain of being a mother.
She said: “The fact is she didn’t notify the council the landlord was the father.
“I would say that it is something obvious to everyone that you should notify the council of.
“She has struggled with her daughter and she does struggle with depression and since her daughter’s birth she hasn’t been keeping well.
“She is doing her best and is looking after the child herself.”
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