File grandson tax he's in college and I put no 1can claim him. I have file adj.taxes.Someone else can claim him.Do I need to mail his parent taxes? can I file them efile?

[IreneS · Accepted solution]

No - You won't be able to e-file the parents tax return with the son's social security number on the return as a dependent.  His SSN is already in the IRS computer, attached to his own return, saying he is not a dependent.  It will take the IRS a while to process his amended return.

Print and mail the parents' tax returns with a note explaining that the son has amended his return to indicate he IS a dependent.