Why Mothers Go Gray

I really wish I knew what is happening in my poor little SuperToddler's mind when she goes from sound asleep to the banshee scream from Hell in 60 seconds flat.  I know she's not having night terrors; she falls back into sleep just about as quickly as she left it, and goes sometimes for several hours before this happens again, or it may not happen again the whole night.  But she's done it at least once a night for nearly a week now.  No major changes in our day-to-day existence have arisen to totally unbalance her world.  If I go into her room to check on her, she responds to me, and seems actually to have awakened--in fact, she has more than once dismissed me with a quick kiss and a forceful, "Night-night!"  She's extremely sleepy, after all, and wants to get back into her bed.  I know the feeling!!  So basically, we've got a blood-curdling shriek that rips my mind out of sleep and my body out of bed in one fluid, terrified motion, only to then have Brigid immediately return to slumber.  Meanwhile, I try to figure out where the several years of my life span that just fell off of me rolled to under the furniture so I can pick them back up, along with what's left of my quickly shredding brain.  I then try to fall back asleep while simultaneously trying to ignore the fact that just about the time that I do, the whole process may start over.  She's been to the doctor recently; I know she's healthy.  I researched all this online, and found answers I already knew--teething, and maybe the occasional nightmare.  Knowing all that doesn't help that much at 4:00 a.m., though I'm grateful to be assured that she's okay and this stage will pass.  It's just been a long week.