Hola Amy,

If the verb that follows cuando is in the indicative, the sentence will refer to something that has already happened.

However, if the verb that follows cuando is in the subjunctive the sentence will refer to something that is yet to happen in the future.

So, in the sentence you are referring to, the verb used after cuando is abre (indicative) rather than abra (subjunctive) because the sentence is describing something that has already happened. '...she often gets perfume' tells us that she has opened her presents in the past.

Clara :)