When I went to get my and my husband's SIN, Service Canada said my 18-year-old son (now 19) can't get an SIN because his study permit doesn't have the condition that allows him to work. I am now filing taxes, and because he is 19, he can't be my dependant and must file taxes on his own, but he doesn't have an SIN, so I'm not sure how he would file his taxes. He doesn't have any income, but we wanted to file his taxes in case he would be eligible for any benefits. What should we do?