Do you also know about if ever the adult child is already receiving disability benefits in his own record, can he still get benefits on my record?
He still should check if he can get benefits on his parent's record. Higher benefits might be payable and he could be entitled to receive Medicare.
If I am widowed, at what age can I have benefits and for what benefits?
She can get reduced benefits as early as age 60 or full benefits at full retirement age. If she's 50 years old she could get the benefits if she's disabled and her disability started 7 years or earlier before your death.