Since your character is growing up, and was presumably born, in
America, I think it could work. Maybe her parents just liked the name. Maybe they wanted her to fit in. People choose names for lots of reasons, and I feel that there's no reason for
Erin not to work on your character. :)
Long story short: Yes, I think it would be fine.
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"I always wondered if her poor relation was named Proletariat". -Bear, on the name Gentry
You fill up my senses
Like a night in the forest
Like a mountain in springtime
Like a walk in the rain