This is a Zelus luridus - or Pale Green Assassin Bug.  I believe this is an immature one.  Being "True Bugs", the babies of these insects look like small versions of the adults - without wings.  Most insects go through different stages - egg, nymph, pupa, before appearing as an adult that most of us recognize.  True Bugs
grow into adulthood without going through these changes.  In addition they eat the same food as the adults (unlike insects like butterflies,
whose babies ((caterpillars)) eat leaves).
Here is an explanation of these processes:
https://askabiologist.asu.edu/explore/true-bugs

And here is information about the little bugger who bit your child:
https://arthropodsofmaine.wordpress.com/2012/08/14/unknown-green-stick-insect-2/

I hope this is helpful.  Please contact AaE again if you have further questions.

WOW, thank you so much for your fast reply and YES it's name sure does match it's bite.  My daughter is 11 and it brought her to tears, she said it was worse than a bee sting.  Should I be on the look out for more of these critters?  This happened while she was just sitting in the living room.  

Again, Thank you for getting back to me to quickly.  DiEtte

It's getting late in the year, so hopefully these bugs will soon cease to be a problem.  In spite of the unhappy experience you've had, these insects are beneficial in our gardens and fields.  They consume lots of harmful insects.They are rather uncommon and it's possible that you and your daughter will live out the rest of your lives without ever encountering another one.  Here is a quote from a University of Missouri article about Assassin Bugs:

Avoiding our harmful assassins involves taking simple precautions. Exclude them from your home by repairing window screens, applying weatherstripping, and sealing other openings. Use yellow bulbs in porchlights, and dispense with bug zappers. Do not camp or sleep inside caves, barns or other sheltered areas frequented by masked hunters, corsairs, and conenoses. To avoid a self-defense bite, gently brush away any bug that lands on you.

The beneficial qualities of assassin bugs far outweigh their negative potential, and learning to get along with these indispensable predators is in our own best interest.

Good morning, I'm pretty sure I just discovered an adult assassin bug in my house.  I have to admit, freaks me out a bit!  How many are in here???  I've attached a few photos, sorry...he's a bit smushed!

If it's not the assassan bug, what is this?  I was looking at the article you sent me back in October and it seems like it's the same bug, just an adult this time.

Please advise, DiEtte

The critter in the photo is too mangled, and the resolution isn't good enough for me to pick out identifying details but if you google Assassin Bug and look at "Images" you should be able to verify its identity.

Since these bugs produce only one generation per year - and they tend to be solitary and somewhat nomadic -  there probably aren't lots of others in your house.  They are coming in from the outside.  Controlling them indoors involves thorough cleaning and vacuuming to reduce other prey insects, caulking areas that may be open to the outdoor, keeping pets indoors.  Here is another publication that contains information about keeping them out of your house:
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7455.html