little brother reaching for dust in the sunlight

I'm looking for an older John-Denver type country song (but I can't remember for sure who sang it!) with lyrics in which the singer recalls his childhood in a cabin with his little brother who wasn't "quite right" and would reach for dust motes in the sunshine . . . the social workers eventually took him away. Does this sound familiar to anyone? Thanks!

I think the song you're looking for is "Rocky Mountain Music" by Eddie Rabbitt

Wow, thanks! I love you!!!