NEW YORK ( TheStreet) -- We're nearly unanimous on the issue of estate planning in the event of the death of a loved one. BMO Management, a Chicago-based wealth management firm, reports that 90% of U.S. adults say estate planning "as an important topic to discuss." So why, in the same survey, do only 19% of adults say there have been detailed discussions on estate planning needs with their parents? OK, there is always the death issue -- nobody wants to discuss their own mortality, or the mortality of a family member. But if you don't have that discussion, you're inviting big trouble from a family financial planning point of view. The Family Conversation You Should Not Avoid: How to Discuss Your Legacy. Parents are reluctant to talk about passing their wealth to future generations. Only 33% of U.S. parents say they have had "in detail" discussions about estate planning with their kids, the BMO study says, although that's significantly higher than their adult kids perceive. That lack of communication is really inviting trouble down the road. "Will your relatives and friends remember their period of loss as one when they were comforted and supported by each other, or will it be a divisive and difficult interpersonal experience?" asks Stephen Williams, a vice-president of financial planning at BMO Private Bank. "One of the best ways to create a legacy is through conversations with family, heirs and beneficiaries to foster lasting positive memories." Although those conversations aren't easy, given the serious nature of the subject matter, they have to happen -- the sooner the better.