姉ちゃん (nee-chan) is Japanese for older sister
Assuming that Kurei is the name of the sister is would be along the lines of "Domo arigato Kurei-neechan". Of course, you can also drop off the domo and just have it be "Arigato Kurei-neechan" or just "Arigato neechan". Hope that helped ^^
A common way to say 'thank you, big sister' would be ありがとう、ねえちゃん (arigatou, neechan). If, for whatever reason, you wanted to speak more politely, you could say ありがとうございます、お姉さん (arigatou gozaimasu, oneesan).
The way to say "older sister" isoneechan (pronounced "oh - NAY - chan") = Familiar formoneesan = Honorific formane = Humble formYou can also take the "o" off the first two to make it just neechan or neesan, but that's more general "sister" rather than for an older sister.For younger sister,imouto = Basic formimoutosan = Honorific form1. my older sister is ane2. my younger sister is Imooto3.your younger sister is Imootosan
姉 = ane, which means older sister (in general). 妹 = imouto, which means younger sister (in general). 姉妹 = shimai, which means sister[s].
姉妹 (shimai) means sister.妹さん (imōto-san) means little sister.お姉さん (onē-san) means big sister.愛してる (anata-o-ai-shite-ru-imoto-san) means I love you little sister
There are a few different ways to say 'older sister' in Japanese. To refer to one's own sister, you would say 姉 (ane). To refer to another's sister or to address your sister directly, you would use either お姉さん (oneesan) or ねえちゃん (neechan).