If you’re in a second marriage or part of a blended family, there’s a good chance your estate plan doesn’t match your real life. And that can create conflict among the people you care about most.

I recently spoke about this with Harry Margolis, an estate planning attorney and author of “Get Your Ducks in a Row.” His first point was simple: Start talking now. Families get complicated. Second marriages, stepchildren, big age gaps…if you don’t talk through your intentions, the law falls back on a traditional family model that probably doesn’t fit your situation.

Margolis said the biggest mistake couples make is assuming everyone remembers the same verbal agreement years later. They don’t. Put it in writing. Even an informal written agreement is better than nothing.

A prenup isn’t just about divorce, he said. It’s one of the most powerful estate planning tools for blended families. It clarifies what you own, what your spouse owns, and what happens when one of you dies.

And here’s a key point. If you have children from a first marriage, consider leaving them something right away. Don’t make them wait until your spouse passes away. A trust can help, but it’s not perfect, especially if your spouse is much younger or remarries.

Think about your IRAs, 401(k)s, and life insurance. Beneficiary designations override your will. So make sure they match your intentions.

Blended families can thrive with good planning. Talk early, document everything, and work with a qualified estate attorney. A little clarity now can prevent a lot of conflict later.

Below is a transcript, edited for clarity and brevity, of my interview with Margolis.

Robert Powell: Are you in a second marriage or perhaps a nontraditional family? What are the estate planning implications of that? To talk about this, we’re joined by Harry Margolis, author of “Get Your Ducks in a Row.” Harry, welcome.

Harry Margolis:  Good to see you, Bob. This is an interesting topic.

Robert Powell:  So where do we begin?

Blended families have special considerations when it comes to estate planning.

Why second marriages require more planning

Harry Margolis: Begin by thinking about it and talking to your partner. Our laws are set up with the presumption that everyone marries once. It is the “Ozzie and Harriet” model. They have two perfect children, everyone gets along, and there are no problems.

Reality is different. People get married, divorced, have children with different partners, and build blended families. Stepchildren enter the picture. When that happens, estate planning becomes more important, and you really have to think it through.

If it is a second marriage, you should consider a prenuptial agreement. A prenup outlines what each spouse owns, what happens if you divorce, and more importantly for estate planning, what happens when one spouse dies.

Related: What Medicare Part B price hike means for your 2026 Social Security

You also need to ensure your estate documents reflect that agreement. And know that you can change these documents. A prenup written 10 years ago may no longer apply if the relationship has become more permanent. You can revise the agreement and update your estate plan.

If you do not talk these issues through and set up a plan, real problems can occur. These are the cases where a lot of bad things happen. You see disputes between sides of the family. One spouse dies, everything ends up in the surviving spouse’s name, and eventually passes only to the survivor’s side of the family.

People may become estranged because of how things unfold, especially when an “evil stepmother” or “evil stepfather” is perceived to be involved. So the most important step is talking with your partner.

Put agreements in writing

Harry Margolis:  You want to talk through what you want to happen if one spouse dies or becomes disabled and needs care. Then put it in writing. Whether it is your estate plan, an agreement between you, or a formal prenup or postnup, getting it in writing is critical.

Our memories are fallible. My memory of an agreement from 10 years ago will differ from yours. We may both act in good faith, yet recall different things. Writing it down eliminates that. You may later decide what you agreed to was crazy, but it reflects your state of mind at the time.

Implement the plan. This is especially important if you are not in the “Ozzie and Harriet” situation.

Protecting children from a first marriage

Robert Powell: You’ve likely seen situations where a husband or wife has children from a first marriage and wants to ensure assets go to those children. Beneficiary designations are one way to do that. You can name your children from the first marriage as beneficiaries on an IRA, 401(k), or life insurance policy.

Harry Margolis: Yes, that is one option. Another common structure is for assets to pass into a trust when the first spouse dies. The surviving spouse gets access or income, and upon the survivor’s death, the assets are divided between the two families.

This makes sense in theory. But there are problems. If there is a large age gap, the children of the first spouse may wait a long time. And during that time, many things can happen. Assets may be spent down entirely. They may drift to the surviving spouse’s family. Or the surviving spouse may remarry and change the plan.

That is why it often makes sense to leave something directly to your children when you die, rather than making them wait. It avoids forcing them into a position where they need to “play nice” with a step-parent just to protect their inheritance.

When family disputes escalate

Robert Powell: And you’ve seen cases where children from the first marriage sue the surviving stepparent.

Harry Margolis: Right. Sometimes the stepmom or stepdad is not doing anything wrong, but the children believe they are. We had a case like that. The children thought their father was much wealthier than he was. The stepmother made a few procedural mistakes in probate, but she did not steal anything. A lot of money went to lawyers before the children accepted the truth.

Prenups and professional help

Robert Powell: It sounds like the best advice is to get a prenup and put everything in writing, ideally with the help of an estate planning attorney.

Harry Margolis: Yes. Although even writing your own agreement is better than doing nothing.

Related: Don’t let your estate plan slip: beneficiary designations matter