It's different. I wouldn't say weird, wrong, or super cool.
But not everyone experiences the bond extremely close siblings have, and tattoos, imho, are best served to represent that very thing - what means the most to you in your life.
Me and my sister have a very close bond. Actually, my immediately family has amazing bond - parents married for around 25 years (can't remember exact number

), me and sis fought as kids a lot but, that's kids being kids - now we're extremely close, got that way as we both matured, sadly, just as that was really starting to happen, she moved out of state with her now husband, and then moved even further away to Texas. But she's super happy and that makes me proud.
But names as tattoos - only names, if I ever get any names, will be my last name or family crest. I'll get personal names as a means of remembrance though, if I go that route at all.