Hello again, Sybel. The following provides the grounds and a form you should complete and file with the court in order to prevent a garnishment.
Pursuant to MCR 2.612(C)(1), a party may be relieved from a final judgment, order, or proceeding on any of the following grounds:
(a) Mistake, inadvertence, surprise, or excusable neglect.
Here is a link to a case which sets out this section of Michigan code:
This would typically constitute the grounds on which you would file a motion to set aside the default judgment and your argument would be sound since your son passed away.
Here is a link to a form document used by MI courts to set aside a default:
I hope this helps clarify the situation for you. Please remember to rate my service once you have all the information you need. If you have any other questions, please ask me – I’ll be happy to respond. Thank you!