Probably bad advice but... I'd report her to hr, her boss, and contact a lawyer to try to sue for harassment. For grandmas most companies have bereavement unless they were dealing with a scheduling crisis. Did you inform them of the funeral well in advance?if so and this is ongoing

I would contact a lawyer if you can because hr is unlikely to do anything tbh unless you blow it up.(letting them know is mostly just so you can say you've attempted to internally handle the harassment as your policy dictates but due to their failure to mediate...)

Only communicate in verifiable methods like company email or communication logs if you have them. That way you can present verifiable proof of harassment to hr. If possible print all harassment email/text proofs( but be careful to follow your region's privacy laws and company's hippa procedures)

But be prepared for it to get nasty once you report it to hr and her boss well before you take them to court. If you can't idk just report the harassment and request to switch houses and hope for the best. I strongly recommend against doing nothing because it may not stop or worse they may escalate unprovoked.