Lullaby
noun
A song you sing to protect your child while they sleep is called a lullaby.
The readings for this word are all kun'yomi readings. You haven't learned this reading for 守 yet, so here's a mnemonic to help you:
When you finish singing a lullaby to your child they always ask for more (もり). It doesn't matter how many you sing, they always want at least one more before they will fall asleep.
これは日本の子守歌です。
This is a Japanese lullaby.
アメリカで一番有名な子守歌は何ですか？
What's the most popular lullaby in America?
子供のころ、母によく歌ってもらった子守歌なんです。
That's a lullaby my mother often sang to me when I was a child.