Two things in addition to what has been said:

- a visit to the Planned Parenthood or her GP or her OB-GYN; she needs to explain that she lived with a guy involved in high risk behaviors (Craigslist etc) so could the doctor or nurse practitioner please administer a full panel of tests for sexually transmitted infections

- you and your daughter, each, need to send the ex bf a firm, clear message saying that he is not welcome in her house and that his written communications to both the daughter and the mother are not welcome and any such communication now that he has been put on notice will be considered harassment and immediately forwarded to the police.