The brothers were almost alike but had minor differences. They had the same acts, attitude, good outfits and other things. However, there was a difference that really bothered Terzo. Their hair...

Terzo spends a lot of time fixing and doing his hair, which always ends up flat, and it annoys him.

As for Copia, he naturally had a lot of volume in his hair and he didn't even spend as much time as Terzo to fix it! Which is what Terzo is honestly jealous of.