Found out my brother has been sexually involved with a minor

my 20yr old younger brother has been involved with a 13 year old female. at first they were talking on facetime and his excuse was “i can’t make friends my own age”. it has been getting progressively more disturbing as time has went on. my neighbor which is actually the child’s older sister came to me with this information the other night. he has been seeing her and sneaking out to go see her. he has provided her with numerous vapes. as well as being caught talking sexually to her such as “oh babe you gave me blue balls for the past 3 days” i am beyond mortified. no one knows the true extent of what has happened between them but im beginning to believe the nature of their relationship is far more heinous than originally thought. i took it upon myself to file a police report against him as well as a dcs report. i am currently pregnant with my first child and live in home with him. i am terrified to bring my child home to someone who could very well be a chomo. i am sure i did the right thing because this 13 year old child’s safety as well as innocence is at risk due to my horrible, disgusting brother.