:cool: Tax re-check only for 3 years the longest can go back for 5 years.If you are residence in Canada you may get child tax benifit(if your child saty China in a short period).But you whole family are not in Canada you better don't take this risk.If you have a telephone number under your name and electricity bill you may can try it.If you have own house and electricity bill and phone number for sure you can try it.