[EvilEvilKitten]

That depends upon your parents. Think about it. What have they told you about sex? How do they handle exposure to risque or sexy scenes in the media? What seems to be their opinion on sex education in school and so on? How do they react to the current run of teenage girls' fashions?

It is difficult for most people to STFU when they witness anything - even adults. So it is best that YOU learn NOW - to seriously consider consequences. Do NOT try to justify speaking because "it is for her own good". Because it may not be. The outcome could be horrendous. Also remember that your sister will never forgive nor forget that you ratted her out and will always question your motives for doing anything forevermore.

TALK TO YOUR SISTER. Ask your sister if BCPs and condoms were used. If so, then fine, say nothing to no one. If NOT, then you had better send her here to us - so she can learn better.

Do not be thinking your sister is running into trouble. She's doing pretty much what other 15 yr olds do. She's exploring. As long as she doing it safely and with due concern for the pregnancy and health issues involved - she's fine.