New answers tagged eu-citizens
Not familiar with specifics laws of Guatemala, but in general: You can usually enter your country of citizenship on any ID conclusively proving that citizenship (with varying degrees of hassle). An expired passport should suffice. However, she'd almost certainly need to obtain a new Guatemalan passport in order to leave (i.e. could not use the Spanish one ...
According to Visa Waiver Program Wikipedia page (I assume you can join the Visa Waiver Program) Passport validity The standard requirement for passport validity is 6 months beyond the expected date of departure from the United States. However, the US has signed agreements with a number of countries to waive this requirement. 
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