"Right now I'm at grandpa's" (source context)
In this case the speaker is on the phone so his speech is casual and fragmented.
I already have an idea of what the sentence means, what I am hoping to understand is:
- What なんでって is a contraction of?
- And what it is doing in this sentence grammatically? What nuance does it add?
I know that とこ is a contraction of のところ but what is なんでって, is it なので? I know って is often と or sometimes という but that doesn't seem to make sense in this context, at least to me as a beginner.