Is this normal?

Im a normal girl, well a little bit different a while ago a family friend came to our house because of something going on at home, shes now like family she lived with us for now like 6 years we go to school together, we're planning to go the same uni, and we share our every secret its like shes now my sister. For a while shes bern saying shes going to go to her friends house (and ik she doesnt talk to anyone in school and she doesnt use social media) i found out (since we sleep in the same room) there was a positive pregnancy test, and when my parents found out she said it was mine, what shoukd i do?