Is it right to block someone even if its your family if they send you harassing messages?

I blocked my sister. She would mumble things and cuss me out quietly and always does this and then she DENIES it and plays innocent and she's an ADULT and then she'll act manipulative and say 'you're hearing things'. She's extremely condescending, so I blocked her. But I think she can still make calls. I'm using the iphone X. How do I block someone from laving voice messages? I can block her calls but it still goes to voicemail.

Added (1). Also do you really think that people will admit something after they've done something wrong? She lied about it, i texted her back and said i can hear you when you're quietly cussing me out and walking by, she ALWAYS does it and acts like nothing happened and gets away with it.

Of course, I condone it actually.

Your sister needs help, she is a problem. Try to ignore her and don't let it get to you. If you react to it, she will like it. If you don't react and just try to ignore her, that will make her enraged. Let her get enraged because you won't be doing anything wrong.

There's no obligation for you to keep your sister in your inner circle, if doing so does not feel right for you. If you feel harassed, threatened or uncomfortable with your sister's behavior, create that distance and protect your wellbeing. Do what is right for you.