Massachusetts inheritance laws do a reasonably good job of planning for you if you are in a traditional or typical family- two married parents and children who are from the same relationship and there are no special wrinkles to your situation. You should still have a plan- the state's guess is just that- but you need to take special care if your circumstances differ. For example
Blended families have to do more planning to make sure each partner has taken care of their own children.
If you have a child with special needs, there are also additional pieces you will want to add to your plan to make sure you can take care of them and not make them ineligible for benefits.
If one spouse is a non-citizen, there are also unique estate tax considerations you will have to plan for.
If you have been through a divorce, your plan will need to be updated.
If you have relatives who would otherwise be heirs that you specifically do not want to inherit, this too should be discussed with an estate planning attorney.
Learn more here about special circumstances in estate planning.