She'll get better soon, you know.

Literal

She [topic-は] soon good become [you-know-よ].

Casual reassurance, in plain non-past form (a statement of expected future). The sentence-final よ adds informational assertion — 'I'm telling you / you should know' — common when offering reassurance, advice, or new information. すぐ without に is more casual; pairing it with よ makes the whole utterance friendly and confident, the kind of thing said to comfort someone worried about a loved one.