Closest Foreign Language To English?

I always thought it was German but my sister just told me that it wasn't.
So I went to go ask google and they couldn't tell me!
(Gee thanks google. Has answers to everything my butt.)
So then I resorted to Cha Cha and THEY tell me that no one has ever asked that. So my question has remained answer less so far.
So now I'm here asking you guys.
What do you guys think is the closest language to English?
I mean when I listen to people speak German I can hear some English words in there.
Maybe I'm right and my sister is wrong.
I don't know.
What do you guys think?