I agree with the previous answers. I will add that you will receive back pay from the first day you submit an application. So even though the process can take time, your son will eventually get all money he is entitled to.
Are you saying you need to file disability for your son? If so, you need to physically go to a local office, and the sooner the better. If you cannot go to a local office in the near future, you can file for disability online. Although, this can be a lengthy and arduous process.
I am not employed, but I was there today. They took appointments first, so I would say yes. I also think u can call to schedule an appointment.
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