Q: activation lock

my sister iphone cannot be used when she upgraded ios 7 to 9(iphone 5s),because activation lock,seems like she forgot her apple id password and she uses icloud email to make her apple id,when she and i try to reset password the email that to reset password was sent to the current apple id which we dont know the password how can i reset my password if the email sent to the email i cant even open,i dont know how she make the apple id,well she only 13 and the apple id has no meaning to her,i mean she just use iphone to play.now the iphone locked we dont mind about the data inside we just want the iphone unlocked,i cant even set the iphone as new iphone.she dont mind use that iphone as new iphone,i already searching the solution and cant find any,can u guys help me and my sister?sorry for my bad english,thank you...please reply ASAP