Heart problem

I am worried of my sister Eme. She is only 15 years old and she have a heart problem I don't know why and how she got it. Mama just text me on the phone the other day to let me know about her and I just feel so bad about her. Hope she's doing fine. They are going to bring her again to the doctor this month to check her up again. I don't know how much it cost but I am just hoping that she is okay.