I've been checking the window temp. but it's ok. It's still pretty chilly down here most the time. I've moved the sick plant into different seedling mix. Didn't want to disturb it but it's already pretty bad. It's going down just like my other ones did. But I'm testing the new seedling mix with 2 new babies. Maybe it wont happen to these girls. I'm going to keep looking into what the culprit is though.