Midnight at 120, 3 am at 320

Two nights ago my daughter went to bed at 120. When we tested her in the middle of the night she was over 300. SHe hadn't eaten for 6 hours. 

SHe was high all day yesterday after that. It was a new site. 

What can cause her BG to rise in the middle of the night like that? Is it probably the new site?

When did you change the site?  Did you correct the high at 3am and she was still high for the rest of the day?  If that's the case it could be a bad site (maybe the canula kinked) or she could be fighting off a cold or getting ready for a growth spurt (both cause insulin resistance).  

You may want to change the site to rule that out.  Try to test a little more often and correct as needed.  If blood sugar stays higher than ususal for 3 days in a row, contact your doctor about increasing basal rate slightly.    

I've had diabetes for almost 35 years and still need periodic basal insulin adjustments.  It's just part of the exciting world of diabetes mangement.   Take care.  

We have been increasing her basal and I/C ratio over the art few months. She uses twice as much insulin as she did in September. I think its because of the lack of exercise in winter.

The site was new that evening.

That makes sense.  I usually increase my dose quite a bit in winter too.  In summer I'm more active and the heat also lowers my insulin needs.  

Sounds like you're doing a really good job figuring everything out.  Having diabetes makes most of us quick and creative problem solvers because we have to deal with so many variables.

It turns out she was coming down with a virus. We increased her basal 30% temporarily and she her BG is better now. Sore throat and cold made her BG jump.

Well this is a hunch of mine but a while ago I continulously woke up in the 300's even when I went to bed at a perfectly normal number and taking my lantice. My Dad started waking me up at 2AM to check and as it turned out, I dropped to 40 around that time and my body wasn't waking itself up. So If you fall low at night and don't wake up then your body uses it's own energy or something (I don't know the exact science.) And this can cause spikes, so try testing between the normal numbers and highs.