I would suggest that you first talk to your partner and agree between you both what your role is. Discuss how comfortable you both feel about your boundaries as a stepdad.
Does your role include disciplining the stepchildren?
In my own experiences as a stepdad, I would advise leaving all the discipline to the biological parent. Just offer advice if asked and support your partner in their decisions. Try to discipline as a united front as this is very important in your blended family so the children know you are both together on making these decisions.
Grow into your stepdad role and build the trust with the stepchildren before exercising any of your authority. You don’t have to be a dad, just a role that suits the needs of your family. You might start off as a friend to your stepchildren and gradually grow to become a stepdad. Your role will inevitably involve day to day responsibilities such as making sure they are fed, clothed, safe and even loved.
Your role may not be what you assume it is and that’s okay. Take things slow and don’t force things to happen. Enjoy your family and let your stepdad role grow with time. Be patient and see where your new stepfamily journey takes you.
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