Intimate
Friendly, Close
い adjective
Your parents are very close to you, most likely. They are your closest relatives. They are the ones who are intimate and friendly with your affairs. They want to know everything!
したしい
Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You didn't learn that reading with this kanji, so here's a mnemonic to help you:
Those who are most intimate with you hang out with you even when you're doing gross things, like sitting on the sh*tter (した). Gross, your family is.
まだ親しい友人にしか話してないの。
I've only told this to close friends.
「親しき仲にも礼ぎあり」って言うでしょ？いくら親しいからってトイレはのぞかないで！
They say, "A hedge between keeps friendship green," right? We're good friends, but don't peek at me when I'm on the toilet.
ちょっと、コウイチ。落ち着いてよ。 親しい友人たちに誰か80セント貸してあげれる人がいないか聞いてみてあげるから。
Oh Koichi. Calm down. I’ll ask my close friends if anyone can lend you the 80 cents.