convenient sharing

[in Addi and Libby's bathroom]

gp: Is that glitter on the wall?
agp: Where?
gp: (pointing to spot about 3 feet up the wall) Right there? It is.
agp: No, it's not. Libby did it.
gp: Addi, you're the one with the body glitter.
agp: No, it's mine AND Libby's. I just decided.