While we’re at it, we may as well recognize that there were 4 slave states that did not secede, and name the other two: Maryland (yes, THAT Maryland) and West Virginia which seceded from Virginia to remain with the union much the same as I would suspect Inland and Southern California to secede from California if the latter decided to break away.
Maryland couldn’t secede - Lincoln garrisoned Baltimore with federal troops fearing that DC would be surrounded.
Are you counting Missouri as out then?