Having a trust is helpful but it is not guaranteed to prevent litigation between family members over an estate, according to Barron's in "Are Fiduciaries Setting Themselves Up to Be Sued?"
Most people with trusts designate a family member to be the trustee. However, if that family member does not get along with other members of the family who are the beneficiaries of the trust, then the same family dynamics that can lead to fights over a will can lead to litigation over the trust.
Trustees have a legal duty to act as fiduciaries and to manage the trust in the best interests of all beneficiaries.
What many families end up seeing is that a beneficiary who does not get along with the trustee, for whatever reason or no reason at all, will look for a way to sue the trustee for breach of his or her duty.
There are ways to make these sorts of lawsuits less likely.
Whether it is a trust or a will, an estate planning attorney can advise you on creating an estate plan that will meet your unique circumstances.
Reference: Barron's (June 6, 2017) "Are Fiduciaries Setting Themselves Up to Be Sued?"