This message is for the mother who has two children and allows a thirteen year old to act older than her age to the tune of a 20 year old.  This is not the story of the author but an attempt to answer a question of a concerned older brother or sister.

If you are in a family that has a mother as the head of the household. it is your job to do what you can to help out.  Your job is to set a good example for the thirteen year old.  If you are old enough to notice that something is wrong, then you are in a position to make a correction.  It is obvious that the child has no respect for the mother or she would not be acting inappropriately by acting so much older than her age.

A thirteen year old does not have the maturity to realize that her actions are not appropriate especially if the mother may be overwhelmed with other things that are going on.  Most mothers main concern is to care for the kids.  But there are all sort of things that can get in the way of motherhood overload and cause the mother to think that as long as the kid if fed, clothed and have a place to stay maybe the older child can help out. 

That is where you come it.  You can tell you thirteen year old sister that she is attracting company that is not appropriate and there is a danger of dressing a certain way that will attract men of all ages.  Call  a social worker and ask for help.  Do not try to get assistance on line by sending out request such as this.  You need to get help and help is as close as the nearest telephone.  You can not go it alone because it is obvious that you do not have the answer because of the request made on line: "What to do about a thirteen year old who mother allows her to act and dress like a twenty year old."

You can not home train an adult even if you were not a child.  You can observe and you can call for help.  There is no need to call Child Protective Services although that may be an option if you have no way of getting in contact with a social worker.  But as an observer and member of the family. you are the one to take action is you are of age to do so.  If you are not of age to make a call, then consult with family members and let them know what is going on.  Let them know your distress at having to see you sister raised up in such an environment of no rules barred. 

You are witnessing a situation that can not improve unless action is taken and your nearest telephone is the best place to get help.  Call your nearest social worker or if conditions are out of control, call child protective services,  These agencies are here to help and also talk more to your family members about the situation that is going on with the thirteen year old.