Grant continued: "Smoke and mirrors cannot hide the elephant in the room. Out of respect, tradition, and humanitarianism, the #Markles should be invited if 2000 complete strangers are invited. Our uncle who got her the internship, brother, me, best friend of 30 years Nikki Priddy, nephews. Fact."
Markle and Prince Harry will tie the knot at a ceremony at Windsor Castle on May 19.
51-year-old Grant, who is confined to a wheelchair due to multiple sclerosis and lives in Ocala, suburban Florida, with her husband Mark, has previously said the princess-to-be has abandoned their father, Tom Markle, who filed for bankruptcy in 2016 and now lives in Mexico.