the daughter playing soccer with adults

I just saw this film a few hours ago and really enjoyed it. I saw it on Netflix but was holding back watching it because I thought it was going to be a bit heavy and I want it the mood for it. Bit I'm glad I did as it had a light hearted touch despite the subject matter.

So anyway, I get that the daughter pretended to be a boy to play football with the local men's team bit isn't she like 12? And how can a 12 year old pass as an adult, even if it was as an 18 year old? She looked very young and 12 during that match to me. So since this is based on a true story, how did they pull that off in reality?