On 8/2007 My wife, our 2 sons (less than 21 years old in that time) filed I-485 application to register permanent residence based on my wife employment. Now, due my wife change her employment and the employer revoque the I-140, uscis has rejected this case mailing a Withdrawal Acknowledgment Notice. Some part of the notice says "If at some point in the future you wish to pursue the benefits provided by this application or petition, you must file a new application along with all applicable fees and evidence.". What that means that paragraph ? Currently my sons have more than 21 years old. If we file a new application, based in my wife's employment, We can appeal to the child protection related to the previous application? Please let me know as soon as possible.