We hired a lawyer, two yr. later found out he was sueing us 2yrs2mon ago is this misrepresatation?

my girl friend was getting a large seetlement from a car accident. her ex hired a lawyer to sue her. this is the lawyer we have today. we did not know he tried to sue her because it went to her lawyer at the time. 2yr and 2mth ago the settlement was over. we hired this lawyer 2 mth later not noing he tried to sue her. we only found out 2mth ago because we had to do her taxes., thats when we found this doent addressed to my better half and that he was going after 25% of her settlement. know i think why its taken so long to get our place in order his bill was $1000 in feb 2006 and know its $12000. so what can i do ?