What is going on?

For the past several days, Eden has been fighting bedtime. To the tune of talking, whining, complaining, crying, calling out for me for as much as TWO HOURS after she is put to bed for the night. Then, she's waking really early (for her), regardless of the fact that she is getting to sleep so much later than usual. Evan thinks she's maybe going through a developmental leap, and can't shut her mind off enough to go to sleep. I think maybe the four teeth that she has been working on are bothering her. Either way, it is not fun. I'm starting to dread bedtime, because I know it will be such an ordeal.

This morning, she actually did sleep until almost 7 (though, she didn't finally fall asleep last night until 9), but for other reasons not known to me...Sadie woke ridiculously early (6am, as opposed to her normal 8am).

What is going on with these girls? Spring fever?