Do I Have Baby Salvias?

I was dismantling my large containers today when I came upon a few surprises. Six surprises, to be exact.

In two of the three pots where I had temporarily tucked some 'Caradonna' salvia, I found these tiny seedlings that looked like baby sages. One of them was large enough that I was comfortable breaking off a leaf and sure enough it smells a bit like meadow sage, too--just a lighter scent than my larger plants give off.

I'm kind of confused about all of this... how does this happen? The 'Caradonna' salvias were just babies (tiny little plants from Bluestone) and to my knowledge they haven't flowered for me yet.

Could these things have sprouted from some of the roots that were left in the pot when I unceremoniously yanked the plants out to put them in the ground? Or am I being fooled by a clever weed that just happens to look like baby sage and was growing in the right place?

I planted all of the tiny seedlings in my garden beds, but I have no idea if these little guys will overwinter since they're so tiny. Anyone have advice on how to give them a good chance--or do you think I should bring them inside for the winter instead of leaving them out? I would appreciate any thoughts on this... I would love to have more salvias, whether they are true 'Caradonna' babies or some unnamed hybrid between my 'Caradonna' and my 'May Night'!