The same or younger

A few weeks ago, a friend of Erin's from China that was adopted trusted her parents to tell them that she was not the age that the adoption paper stated she was, she has very vivid memories of her life before going to the orphanage.  This child is younger then the stated age.  This was the second one from Erin's orphanage that it was discover was 2 years younger then what the paperwork said.  Both of these girls came to the orphanage later in age, so they know some of the their life history before joining the forever families.  When I told Erin this, Erin told me that it was right about her friend and explained it to me how she knows that.  When I asked her, she states she doesn't know if she is 14 or if she is younger,  said that the teachers told her things that she knows aren't true, but now she doens't now the full answer because she is confused with what is the truth and what she has been told.
According to what Erin is now telling us, she is proably a year to a year 1/2 younger.  Dental records do shows her being at least 12, but not much older then 12.  We won't change her birthday or anything as we don't know anything concrete.  Our focus now is trying to figure out where she is academic wise.  During out talk, it came out that she finished 4th grade, that 5th grade she was gone most of the time for badminton.  We knew she missed some school in 5th grade, Erin is telling me that she missed most of 5th grade.  She also recalls in China being in 3rd grade as a 9 year old and then was 11 yeas old when she finished 3rd grade.  She picked up on ASL so quickly so putting her age appropriate into 7th grade when she came home last year seem to be the right choice.   Her 7th grade was majority focus on ASL with learn some basic spelling words.  This year we trying it with less 1:1, she been doing pretty good in those classes.  I am working with her school and they decided that in Jan. would be a good time to start testing her to see where she really is acedemically, I didn't want to wait that long, but I also understand their reasoning. 
Erin has been doing a lot of questioning since this came out, she doesn't want to be held back, mainly because of her dear friend who will move to the hs (is in the same building, just on the other side) and that she doesn't want to be 20 years old when graduate.  Tonight we got on the topic again of her asking me why we might hold her back, after explaining it to her, she started to tell me that she not good at reading and writing, started to compare herself to her sisters and friends.  As I try to explain to her again what seems like a million times, she only been here for just over a year and this is a new language.  I can' see the walls start going up, so I try to tell her that there is all kinds of games that her 1:1 and I put on the computer for her to help her learn to read and do math, she tells me they are boring, and also tells me that I am to busy to help her learn English and don't sit with her enough.  I said back to her that I help her with her homework every night, and through out the evening if we are looking at something (magizine or newspaper or on line, I will ask her what the words are and tell her the words she doesn't know) but she also need to do some of this on her own and not spend all her time on the computer watchin Korean videos.  She said she likes to watch them.  So after talking back and forth for a few minutes longer, I can tell Erin was getting in that testing mode along with shutting down, so I told her we were done talking for now.  She said ok and left.  She did say good night to me when she was ready to go to bed. 
How do I feel about the possiblity of Erin being younger.  It would explain a lot.  She has a lot of immaturity in her when it comes to relationships.  I have spoken about her dislikes towards men.  She also has issues with relationships with females too, just not as bad as men.  She questions authority a lot and wants to know the reasons behind things.  She may know a lot of some things, but other things she doesn't know much about it and being 14 years old you would think she would.  I always chalked it up to being in the orphanage and being deaf, I am now questioning that it could be because she isn't as old as we thought she was and her brain is still very immature and simple thought process which could explain her attitude towards men.
I am hoping that she will think a littlbe bit about what I said, to understand that she needs to work harder at learning English and there are things she can do that doesn't require me to be there with her the whole time, that these games might be boring at first, but as you improve you English you can play hard games.  She wants to go from point A to point Z without doing any of the stuff in the middle and I have try to explain that to her without succeed.
Please pray for her as she struggles with this and that I was able to get her to understand and motivate about learing English writing.