My adult sibling and I haven't spoken in 8 months after a fight at our dad's funeral. Is it worth trying to repair this?

Usually, yes — but go in with realistic expectations about what "repair" means. Grief makes people say things they wouldn't otherwise, so it's worth separating what came out because of the funeral from what points to a real, ongoing issue between you. If most of what was said was raw and out of character, that's a different repair than if the fight just gave voice to something that had been building for years. You don't have to reopen the fight to reopen contact. A low-stakes message — checking in about something unrelated, or even just "I've been thinking about you, this has been a hard year" — can restart things without either of you having to relitigate who said what. Demanding an apology as the price of admission tends to keep both people stuck. Before you reach out, get honest with yourself about what you actually want. Full reconciliation and a close relationship again is one outcome. Enough civility to sit at the same table at holidays without it being awful is a different, smaller, still legitimate goal. Aiming for the wrong one of those will make you feel like it failed even if it worked. If you reach out and get rebuffed, that tells you something too — not necessarily that it's over forever, but that more time might be needed before another attempt. What rarely works is waiting for time alone to fix it. Eight months of silence doesn't resolve itself; at some point one of you has to be the one who moves first, and there's no shame in it being you.