Learn Portuguese (Portugal): Ela está sempre a chorar na creche.

In European Portuguese, it is highly idiomatic to place short adverbs of time, frequency, or degree (like sempre, já, ainda, or bem) exactly between the auxiliary verb (está) and the preposition a. This "adverb intrusion" breaks up the continuous periphrasis but sounds extremely natural to native ears.

Could I put sempre somewhere else in this sentence, like before the verb or at the end?

Yes. You could grammatically say Ela sempre está a chorar na creche or Ela está a chorar sempre na creche. However, slotting the short adverb between está and a is the preferred choice for rhythm and emphasis in everyday spoken European Portuguese.

I learned that sempre can sometimes mean "after all" or "still". How do I know it just means "always" here?

It depends on the verb tense and context. When paired with a continuous action (estar a chorar), sempre almost always describes a repeated, ongoing habit ("always"). The "after all" or "in the end" meaning of sempre is typically paired with completed past actions, such as Ela sempre foi (She went after all).

Why do we use na here instead of just em creche?