My stepsister is getting married and I am so surprised at some of my jealous feelings. I've been married for 5 years now, so its not jealousy about her being with someone and me being single since I'm married. I just get so upset when my dad goes around saying "MY daughter is getting married". What is so wrong with him referring to her as his stepdaughter? Stepdaughter should not be a negative word. Thats what she is. I prefer my stepmother call me her stepdaughter and if she did call me her daughter it would feel strange. My stepsister became Dad's stepdaughter when she was 14. Its not like she was a child that he raised from when she was little. Dad feels bad that my stepsister's dad isn't in her life so he tries to make it up to her. Its nice that he's in a father role to her, but still he's not her dad. My dad is walking her down the aisle and giving her away. My dad gave me away too when I got married. I am really trying to put aside my feelings and be supportive of my stepsister. My stepsister did make me a bridesmaid in her wedding. I am so surprised at my reaction to this. I thought I had really gotten over the fact that my dad thinks of my stepsister as a daughter. But it hurts. Its like me being his biological daughter means nothing to him.