The only reason Basch denies having any close relations to Austria *cough* when they were kids * cough cough* is because he feels like he failed.

They were so close then grew apart, and Swits hates that for a couple reasons.

First, the obvious, he lost a brother in a way.

Second, he's afraid that Liechtenstein might think that it's okay to go away from him, since it happened to him and Austria. He's already far enough from people as it is, he doesn't want to lose his sister.

If it came down to it and Basch got a second chance, he would've never let Roderick go.