。
She took care of my dog.
Literal
She [topic-は] my dog [possessive-の] care [object-を] did.
世話をする ('to take care of') is the all-purpose verb for caretaking — Japanese uses it across humans, animals, plants, and even objects. Note the lack of a benefactive ~てくれる here: this is a neutral statement of fact, without the warm 'as a favor for me' overtone. The absence of てくれる makes the sentence cooler and more reportorial than 世話をしてくれた would be.