[rich_sasha]

Latvian and Lithuanian are not at all Slavic.

There is a branch that contains both Baltic and Slavic languages, but there's also one that contains Albanian and Greek.

[ardit33]

Albanian and Greek are both completely separate branches, and both unique on the tree (they don't have common cousins like the others).

There have been some attempts to tie Albanian to Germanic, or Greek, or other branches, but they all have failed.

At some point they all are Indo_european, but they split a way ago.