Don vs Larry fics

[endersgambit]

I read a chapter in a fic recently that briefly described Don being jealous of Larry's relationship with Charlie to the point of really disliking him for a while after they met. He resented having another older male figure in his little brother's life, especially one who was so much more capable of understanding Charlie. It was just a passing side-bar in the overall story, but it got me thinking about what a great premise that would be.

Does anyone know of any stories where there is tension or rivalry between Don and Larry over Charlie?