If you die without a will, everything does not automatically go to your spouse. Your spouse gets the first $30,000.00, and splits the rest of your estate 50/50 with your children. Your children would get all their money at the age of 18. There are many scenarios if you are not married or if you do not have kids. The Commonwealth of PA has a will for you that will direct how your property gets distributed if you do not do it yourself.
If you have a minor child, or a Dependant with special needs you must have a Last Will and Testament to name appropriate Guardians and Trustees. If not, the Court, and potentially Family Services will get involved and make those decisions for your children. This can cause families to fight amongst themselves and great emotional harm to the children.