If parents with minor children die, a Guardian will be appointed to raise and care for the children. Parents have the right to designate who will be appointed Guardian--so long as the parents do so before they die. If they do not, then a court will make the decision.
With a life insurance policy, the owner can designate beneficiaries, and at the death of the owner, the policy pays the death benefits directly to the designated beneficiaries. The benefits are paid in accordance with the contractual terms of the policy. So long as a beneficiary is named, no probate is required and the person's Last Will & Testament does not come into play. This is one of the nice benefits of life insurance.
If you are the parent of a minor child, there are two crucial decisions which you should make and incorporate into your estate plan in order to protect your child. The first involves who will raise your child if you die and the second is who will be in charge of the assets or money you leave to provide for your child after your death.