My son's father passed we applied for the social security benefits for survivor can the grand parents apply for it too.

Hi,

Possibly. A parent can potentially be eligible for benefits on the record of their deceased child, but only if the parent was receiving at least one half of their support from the child leading up to the time of their death. For additional requirements for parent's benefits, refer to Social Security's handbook: https://www.ssa.gov/OP_Home/handbook/handbook.04/handbook-0421.html.

Best, Jerry