Families have always been complex, even if a century ago divorce, remarriage and adoption weren't as common as they are today. In any case, you'll want to create a comprehensive estate plan that reflects your family's particular goals and needs.
For example, if you have biological children and stepchildren, then the length of time you've been with your stepchildren may affect how your assets will be distributed. Should your biological children receive more? Or should you make equal provisions because all of them -- the stepchildren and the biological children -- were young when you remarried? The answer will depend on your family's particular dynamics.
To get a clear feeling for those dynamics, it is important to discuss your plans with everyone involved. You can get together as a group, or you could speak with each person individually. Either way, you can likely prevent confusion and possible disputes among family members by discussing your wishes with them and considering their opinions.
If you have a second spouse, then you'll undoubtedly want to provide for him or her. But if you also have children from a previous marriage, then you may want to avoid making them wait for your second spouse to pass away before they receive their inheritance. You can avoid this potentially contentious situation with clauses in your will or by funding a trust for your children.
Finally, it's worth mentioning that members of big or blended families may have very different views about what to do with the family home or other property that has sentimental value. If you're not sure about these matters, then it's a good idea to discuss them with your family to decide on an appropriate course of action.
Source: The Street, "6 Things to Consider When Estate planning for Your Second Family," Kathryn Tuggle, Aug. 7, 2014