My sister in law bought a car unther my Gilr name , my girl as the owner and her i guess as cou signer.?

my sister in law and her husban miss tow payments and now my girls credit is bad, they aready pay for the tow payments behind, Is there any way we can erase that of my girls creidt , mybe a lawyer can help. it;s rerally important because we want to buy a house soon.