Teen parenting expert Rosalind Wiseman answers your tough questions.

Question: I’m 13 years old and my parents are separated. I spend some weekends at my dad’s house and his new family is mean to me. My dad and his fiancée criticize me for being lazy and overweight. They often say they’re joking, but I’m in tears when I get home to my mom. How do I make them stop?

Answer: Unfortunately, I get many letters from kids in your situation and it comes down to one solution: You have to be more mature than your parent. If you want to tell your dad how you feel, bring someone with you whom your dad respects, like an uncle or grandmother. If you have to do it alone, be prepared to have your mom pick you up around the corner from his house in case the conversation doesn’t go well. When you tell him how you feel, don’t bring up everything he’s ever done. Describe patterns of behavior, like he insults your appearance and abilities, or his fiancée does and he backs her up. If he gets defensive or laughs, say, “I’d like to have a good relationship with  you. I have a right to my feelings, even if you disagree with them. How you’re reacting makes me not want to be here. So I’m going to leave and when you want to talk to me about it, let me know.” Then ask your ally to take you home. Remember, your goal is to live in an emotionally safe home. If your dad can’t give that to you right now, stay at your mom’s.

Do you have a parenting dilemma for Rosalind? Send an email to askrosalind@familycircle.com.

Rosalind Wiseman helps families and schools with bullying prevention and media literacy. Her book “Queen Bees and Wannabes” inspired the hit movie “Mean Girls.” She writes the Ask Rosalind column for Family Circle.