單身老貓,please help,Thanks

單身老貓,
My hu*****and got a request from his ex-wife's attorney for a child support case (Himself passed the documents to my hu*****nad after hearing of the court) to give bank account information,statement,register check and a lot of things from 2006. They had divorced for 3 years. Do you think it is reasonable? Can we ignore it since the document was served by the attorney himself? Can we say no to the request since it is not an court order? They asked legal response within 30days. Thanks a lot!