Should I consider my sister's height before getting her a name necklace this Valentine's?

This Valentine's Day, I'd like to get some rose gold jewelry for my sister and myself. I'm of average height and prefer necklaces that sit comfortably on the collarbone. My sister is 6ft tall, and I don't know if I should get her the same size necklace as me. Is it necessary for me to match her name necklace length to her height?