Becoming a stepparent is often marked by unease from the start, especially if the stepchild is older and dealing with his own emotions resulting from his parents' breakup. Whether it is an easy road or not, there are certain rights and responsibilities for stepparents.
In most states, a stepparent does not maintain the same custody rights as a biological parent. This means that if a custody battle ensues for any reason, the courts will often maintain the custody rights of the biological parent. The major exception to this is in the case of child abuse and is examined on a case by case basis. If you are concerned about your custody rights as a stepparent, you should consult a family law attorney in your state to see how the law pertains to your specific situation.
Many stepparents are concerned that their income will be considered making them liable for child-support payments. You should consider that once you get married, the general rule of thumb is that your spouse's obligations are yours. However, most states do not use a stepparent's income to determine the amount of child support due. Additionally, unless a court order is requires it, there is no legal obligation and is often a secondary consideration to biological parent considerations. Some states have created a line between a stepparent's obligation to support the family, including stepchildren while under their roof but not for the time that the child is at her other parent's home. Check with an attorney to determine your state's laws.
When a stepparent enters the picture, he may become the person designated by the family to deal with school or medical issues. This may be a family agreement but has no legal authority unless it is granted by a court. Without that or a signed agreement by both biological parents granting custodial rights to a stepparent, schools, hospitals and other medical providers are not required to release any information or follow the instructions of a stepparent.
The methods used for parenting and discipline in your own home are to be determined by you and your spouse. Your spouse's ex has no say in how you run your household unless child abuse or neglect is suspected. If this is the case, a social worker will be called in to evaluate the entire family dynamic to protect the child and the child's best interest. Just as they have no say about what goes on in your home, you have no say in what goes on in theirs. If you can accept this, you will save yourself a lot of anguish.
It is highly recommended that a stepparent refrain from engaging in any conversation regarding parenting decisions with the child's other biological parent. The relationship between you and your spouse's ex is inherently awkward, even under the best of circumstances. You may exacerbate a situation by contacting the ex to discuss things about your stepchild.