I would suggest that the painting we are looking at with the signature that is not "Sandy" was a reproduction done perhaps for a school project.
I own a print on canvas (looks a lot like an original painting but is not) that was sent to my family in the mail as a gift for ordering books in about 1979 (most likely from Time Life). The painting that has been posted here is dated '89 and I'm sure the print I have is much older than it.
I would suggest that Sandy is the original artist.
I love this painting. Always have. Do you actually have the original painting (not a print on canvas)? Can you see the brush strokes? My wandering mind has often wondered where the original painting is, and who is Sandy? I have been googling tonite out of curiousity but this post is all I have found so far.
..... soooo many owl paintings......