I will add, to an otherwise reasonable answer on Abby's part, that you might try understanding the story of the tattoos and piercings. Kids these days don't just do body modification to piss off their absent grandparents; there's usually some rather well thought out meaning to these things. You might not like the stories, they might unsettle and discomfit you, and, frankly, they might not be stories she needs to share with you. But I will modify Abby's statement here: the grandchild is not underneath the tats and piercings - they are part of the grandchild. If you insist on seeing them as separate entities, then by all means, cut ties, because there will be no peace that comes from that.