I have sole legal and primary physical custody of my great granddaughter. My daughter, child's grandmother died on 9/2/17. Child's mother is receiving social security for disability. mother nor father support child. Can gr granddaughter receive benefits under my daughter's social security record
I'm sorry for your loss.
Assuming that your great granddaughter wasn't adopted by your daughter, she couldn't qualify for survivor benefits on her record unless both of her parents are either deceased or disabled (https://secure.ssa.gov/apps10/poms.nsf/lnx/0200306235). If there is any doubt about whether or not she might qualify, you may want to consider filing a claim on her behalf in order to preserve her potential rights to benefits.
Furthermore, if your great granddaughter isn't already receiving benefits on her mother's Social Security disability record, you should probably check to see if she could qualify. In some cases no child's benefits can be paid on a person's disability record, and in other cases they can. It depends on the disabled person's benefit rate and family maximum, so I can't tell you whether or not your great granddaughter might qualify.