What would they even gain from making something like that up though? Idk... Hard to say without hard evidence and even then there's gonna be people who speculate it being fabricated/faked and doctored in some way. To me it sounds pretty legit, going from them saying they'd share their other screenshots of being harassed to give validity to their claim, something they don't have to do but are willing to anyway, and lets be honest here its definitely something Grace would make her sister do... I wouldn't put it past her: the whole family is shady af.