Since you say she's a citizen of both. If she's in the US right now. For her to travel to Germany all she needs is her blue passport(US) With that she can travel to almost every european country without applying for a visa . Including Germany. All she will need is a flight ticket and boom she's in Germany. And when she's coming back. The same US passport and a flight ticket👍
She needs both US and German passports. If she doesn't already have them probably not. US passports are taking 3-4 months right now. Guaranteed 18 weeks if you pay an extra 60. I am a citizen of both
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