Omg im gonna freak out help please??

My sister who is known for lying and stealing the day before my graduation is taken to the er by my mom. She is having some pain in her left eye. So 3 er trips a trip to an eye doctor and a trip to the neuroligist. nobody can find anything wrong with her. She has been wearing this eye cover on both eyes for over a week claiming the light hurts to bad and she says when she does take it off that she cant see anything but blurry figures. I did look at her phone and I know she has not let her phone out of her hand except for a second. Somehow she cant see but she has somehow been able to delete all of her text messages for the past couple of days. She gets by the way hundreds of text messages because she is subscribed to everything. I doubt highly my electronically illiterate mother has been deleting things for her. So now I am about to miss my state board of cosmetology licensing exam. Because my sister is suppose to get a 2nd opinion from an eye doctor. The first one said her eyes were as healthy as any average persons. wtf am I gonna do if I call my sister out on her bullshit my mom will hate me. If it turns out it is not bullshit I will hate me. My mom is my model for my exam and cant go because of my sister if I dont make it to my exam date I may not get another one for a very long time. It takes forever to get a date. My sister needs the second opinion as my mom tells it to make sure the first doc was about nothing being wrong. She is guilt tripping by saying my sister could loose her vision if she doesnt get treatment soon.