A common misconception about dying without a will is that if you are married, all of your assets will be distributed to your spouse. This isn't necessarily the case.
Dying without a will is known as dying "intestate". When this happens, the law steps in and determines how your assets are to be distributed. In Victoria, the relevant legislation is the Administration and Probate Act 1958 (the Act).
The Act anticipates a number of scenarios. This includes dying without a next of kin, in which case the Crown is entitled to your assets. It also anticipates juicier scenarios, such as where the deceased has more than one partner: for example, where someone is separated from their spouse and is in a relationship with another person at the time of their death.
More conventionally, section 51 of the Act applies. Where no children are involved, it is true that the residuary estate is distributed to the relevant partner.
However, where children where are involved, the partner is not entitled to the whole of the residuary estate. In this case, the partner is entitled to the deceased's personal chattels (furniture, vehicles, etc), plus the first $100,000 of the residuary estate. After this, in simple terms the partner is entitled to one third of the balance, with the remaining two thirds being distributed amongst the deceased's children (to be held in trust until they reach 18).
Think about this. If your estate is worth $1 million (including the proceeds of your life insurance policy and not counting the value of your chattels), and you pass away with a young child and without a will, your spouse will be entitled to $400,000, with the remaining $600,000 being held on trust for the benefit of your child.
Is this the outcome that you want?