。
She looks after my children for me.
Literal
She [topic-は] my children [object-を] care-do [for-me-てくれる].
世話をする (literally 'to do care') is the standard expression for taking care of someone — children, elders, pets, plants. The benefactive ~てくれる explicitly marks that the caretaking is done as a favor for the speaker (or their in-group). Without it — 世話をする alone — the sentence would be merely descriptive; with it, the speaker's gratitude is built into the grammar. The plural-marking 達 on 子供達 makes it explicit that more than one child is involved (Japanese nouns are otherwise number-neutral).