String instrument on “Once Upon a Time” (“To The Moon” soundtrack)

Question

The soundtrack starts off with a piano and then at 0:13 a string instrument (at least I think it is a string instrument) takes the lead. What could it be?

https://youtu.be/auDqBeJP8A8?t=13s

Answer 1

I'm afraid it's not a string instrument. I think it's the 'acoutstic guitar' sound of electric keyboards.

Here's an example: Acoustic guitar sound