Grandchild
noun
The kanji and the word are exactly the same. That means they share meanings as well.
Since this word is made up of a single kanji, it probably uses the kun'yomi reading. You did not learn this reading, so here's a mnemonic to help you:
You are the grandchild of your grandfather. His favorite thing is to call you a maggot (まご). Your grandfather was in the military and is very hard on you, maggot.
孫が生まれてから、毎日がにぎやかになりました。
Ever since my grandchild was born, every day has been lively.
孫に「死んだらSwitchくれる？」って聞かれて目から水が流れ出した。
My grandchild asked me, "When you die, can I have your Switch?" and some water started flowing from my eyes.
孫が泣いてるからなぐさめたら、「YouTube止まっただけ」だった。
I comforted my crying grandchild, only to learn it was just because YouTube stopped.
新しいコンピューターを接続することは、 私の孫にとってはお茶の子さいさいだ。
Hooking up a new computer is a cinch for my grandchild.