An aunt who became her niece and nephew's foster carer has been given over £90,000 backpay after a council initially told her she did not qualify for foster care money.
Mrs D, who does not want her full name revealed, said she has been caring for the two children since 2013 after being asked by local authorities because their parents could not.
But a legal fight broke out over the costs she could claim from Hammersmith and Fulham council.
Speaking out about how the children came to live with her, Mrs D said: "I was told that if I could not care for them, they would end up in foster care.
"I wasn't going to see them leave the family - I agreed to take them on and to be trained as a foster carer.
"I was assessed and trained as a foster carer and began to receive the basic fostering allowance for both children."
Over the years, specialist lawyer Helen Jarvis of Ridley and Hall explained how Mrs D's nephew suffered from neglect with his birth family and this led to "various issues."
She said: "His behaviour was particularly challenging. He soon began to get into trouble with the police and was expelled from school.
"This had a huge impact on the family."
Being related means you do not get the money, council told her
When Mrs D read an article about how related foster carers are entitled to the same allowances as mainstream foster carers, she approached the council about getting an allowance.
Ms Jarvis said: "She looked at the council’s website and found that foster carers in Hammersmith and Fulham received not only the basic fostering allowance for the children they cared for, but also an additional fee element per week per child.
"She asked the local authority why she was not getting these additional allowances - and was told that she was not entitled because she was related to the children."
After taking the case to lawyers, it was uncovered that since 2013, a "kinship foster carers" like Mrs D should not be discriminated against when it came to allowance.
'Quite simply a case of council refusing to fulfil obligations'
After lawyers wrote to the council asking why she had not been paid, Hammersmith and Fulham authorities confirmed Mrs D should have been getting an extra £237 a week per child since 2013.
It was agreed that she was entitled to receive a back dated payment of £90,000 and now gets an extra £474 each week.
The law firm said: "We have heard the same story numerous times.
"Family and friends carers are often told that they are not entitled to the same allowances as stranger foster carers and this is just not true.
"This is quite simply a case of the council refusing to fulfil their statutory obligations."
'Best Christmas present family could receive'
Mrs D spoke about the outcome and said it was "the best Christmas present the family could receive".
She added: "I cannot believe that local authorities are able to get away with this - they knew that I should have been paid the extra money but never told me.
"My life was turned upside down when I agreed to care for my niece and nephew. I never expected having to be a "mum" again."
The carer insisted she is just like every other foster carer, attending the same training courses and being closes monitored as other foster homes are.
"This extra weekly money helps me to feed and clothe them and enables me to afford to care for them.
"They deserve to experience proper family life after their chaotic start they had."
Hammersmith and Fulham Council have been approached for comment.
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