お姉ちゃんが

older sister

→ お姉ちゃん
phrase Rare #27,189
older sister お姉ちゃん is a familiar, affectionate way to say “older sister.” The particle が marks her as the subject and usually isn’t translated directly.
JA: お姉ちゃんが晩ご飯を作ってくれた。
EN: My older sister made dinner for me.

お姉ちゃんが泣きはじめたの。

My big sister started crying.

お姉ちゃんがいたらなぁ。

I wish I had an older sister.

《お姉ちゃんがパンケーキ焼いてくれたわよ》

Your big sister made you pancakes.

— 映画 聲の形 (2016)

お姉ちゃんが?

Your older sister?

— ハウルの動く城 (2004)