の世話は誰が

who will take care of ...?

→ の
phrase Rare #41,463
who will take care of ...? Used to ask who is responsible for taking care of someone or something. The phrase is usually followed by する or its casual forms, such as している or してる, though these may be omitted in casual speech.
JA: 旅行中、植物の世話は誰がするの?
EN: Who will take care of the plants while we're away?

子供たちの世話は誰がしてますか

Who's looking after the children?

ではの世話は誰がするの

Then who will take care of the cat?

の世話は誰がしてるの

Who takes care of the dog?

じゃあネコの世話は誰がするの

Then who's going to take care of the cat?