1. You do not have sex with family members which includes; Mom, Dad, sisters, brothers and first cousins. It is illegal at any age. It is by most religions also considered a mortal sin.
2. Your sister is 13, first see wrong number one then the fact that she is only 13 and should not even be considering having sex at this age.
There is nothing wrong with thinking mom or your sister is pretty or sexy. The wrong comes in when you start to fantasize about having sex with them or start to plan how to have sex with either them.
By your question it would appear you are trying to have sex with your sister. This is very wrong. It is called incest and as I said it is illegal, you can go to jail.
If you have an overriding desire to fulfill this fantasy then please talk to mom or dad and get some help. In our society and most all Western nations, it is not only illegal and considered a mortal sin. It is consider sick to have sex with a family member. [ adviceman49's advice column | Ask adviceman49 A Question ]
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