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This is an easy and inexpensive way to repair American Girl Dolls' hair using household items.
Approximate Time: 4 hours (approx.)
By Debbie A 
You may need to do this multiple times to get full effect, but remember to space treatments apart.
My mom was a doll doctor. She would wash the doll hair with dish detergent. Allow it to dry. Use a curling iron to style it. Spray with hair spray to hold. Use the same process you would with a wig.
By lzygranny from NC
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Here are questions related to Fixing Frizzy Doll Hair.
I recently purchased a Build-a-Bear Pinkie Pie plush pony that I adore! One issue is that her hair is already frizzing some. I tried to brush it, but it made the frizz worse. Is there a way to de-frizz and clean her hair safely? It is doll hair on a plushie. And if I do wash and condition it (if that is safe) is there a safe way to put the curls back in? Please let me know if you know anything about this.
By Susan T.05/19/2014
Isn't that odd! I just spent the morning combing out my oldest daughter's Pinkie Pie. I honestly thought it was a lost cause but I tried anyway. I used undiluted Downey fabric softener, just poured it on my hands and worked it into the mane and tail, gently working out tangles with my fingers as I could. I then used a detangling brush and brushed the ends out first, working my way back to the body.
It took a very long time, and some mats were too far gone and had to be cut out with tiny nail scissors, but she looks fabulous now. I rinsed out the fabric softener and rolled up sections with pipe cleaners. Next day, I took the pipe cleaners out and she looked lovely. Thanks for the tips, everyone!
How do you fix your doll's hair when it is burnt? It is not a Barbie doll?
By Zar from Fresno, CA
I bought 2 used American Girl dolls for my daughter, they both have slightly frizzy hair. Does anyone know of a way to improve the hair so it will be less frizzy?
Thanks in advance for any help!
Jennifer from Bend, Oregon
Yes, send them to the American girl doll hospital. You will need to admit them. Here is a link to the form. Print two of them one for each doll. But ship them in the same box to save money on shipping. http://store.americangirl.com/agshop/static/dollHospital.jsp
Here is the admittance form.