My father cosigned a loan for my niece while he was under medical care and chemotherapy. She basically took advantage of him and now she has not paid the loan since it became due 3 months ago and my father is receiving overdue notices and will have his credit jeopardized. Is there a way they can put this loan back on to my niece. She is working and making money, but just chooses not to pay.
Thank you

If your father is competent, he needs to make his niece tend to her business. He should send her a letter and explain his expectations of her future conduct.

Also as a cosigner they would have to get a judgement against her before they could come after him for non-payment. Are they taking her to court ?

I have to disagree with califdad here. A co-signer is equally responsible for a loan. The lender can go after the cosigner without having to obtain a judgement against the niece.

Dad has two options here. He can either sue that he was not competent to enter into a loan and try to negate the contract.

Or he can protect his credit by making payments on the loan and then suing the niece for the amount he has to pay.

Yes, dad will have to pay to protect his credit and then sue her.

They can sue both and get a judgement against both but his credit will be ruined long before that if it is not paid.