姉 is one of the most commonly used Japanese kanji, and it also has a lot of special readings in addition to the standard onyomi and kunyomi readings.
ONYOMI 音読み
あね ane はは haha
KUNYOMI 訓読み
シ shi
Examples
姉は私のズボンにアイロンをかけてくれる。My sister presses my trousers.「あ、は、はい・・・ごめん、玲姉」「コラ。幾ら親戚とはいえ、私は先輩医師よ?院内ではちゃんとケジメをつけなさい」“Ah, y-yes … Sorry, Coz.” “Hey! You might be my relative but here I’m your senior and a doctor. Keep things straight while you’re in the hospital!”彼女は私の姉です。She is my elder sister.私は姉に相談した。I consulted with my sister.私の姉は20代だ。My sister is in her twenties.私の姉は婚約した。My sister got engaged.彼は姉が3人います。He has three elder sisters.実は彼女は僕の姉だ。As a matter of fact, she is my sister.私の姉を紹介します。Let me introduce my sister.姉はテニスに夢中だ。My sister is crazy about tennis.