。
She was there in the morning.
Literal
She [topic-は] morning-during there was.
Notice that 午前中 here functions adverbially without a particle — Japanese routinely lets time-frame nouns serve as adverbs directly. Compare with 午前中に (with に added), which would add a slight emphasis on a specific point or window within the morning. そこに ('there') marks the location of existence (with に, since いる is an existence verb). The past-tense いた gives the simple narrative observation.