What special issues or topics might a divorced, custodial parent of a six year-old consider in writing a will? What issues or topics might become more important as the child gets older.
The Will Itself
The two main points that are exceptional in this case would be:
(1) to name a legal guardian for the child, and
(2) possibly, depending upon the size of your estate, to name a conservator for the child (like a guardian but for a child's property), or a custodian of property inherited by the child (basically a trustee of a small, simplified trust) or a trustee of a protective trust for the benefit of the child. You might want to name a "trust protector" of the protective trust as well as a trustee, so that there is a designated person to supervise the trustee's conduct during the child's minority who isn't your ex-spouse.
A protective trust will have provisions related to age and conditions and purposes of distributions. For example, it might say distributions according to need for health, education, maintenance and support until age 25, then distribute a third outright, then distribute half of what's left at age 35 outright then distribute the balance at age 45, and it might specify "safe harbor" acceptable purposes like higher education, apprenticeships, weddings, and investing in businesses with a reasonable prospect of success.
You should also probably provide for any family pets. Many lawyers have standard clauses for that.
You may want to identify specific items of tangible personal property that should be reserved for the child's future use at your death (e.g. an heirloom wedding dress), even though it won't be immediately useful.
The guardian wouldn't supersede the parental rights of the other parent, but would have priority together with anyone named by your ex, to serve as guardian if your ex is incapacitated as well.
There really isn't too much else that you can do in a will as there is a deliberate desire to prevent dead hand control of a child.
Non-Legal Economic Options
You should consider buying life insurance and making a trust for the benefit of the child the beneficiary of it to fund a trust for the child if you die. Talk to a financial planner or life insurance agent about it.
Non-Legal Sentimental Options
Of course, there are classic non-legal steps such as writing birthday letters or recording birthday audio/video tapes for the child, if you know that death is imminent and finding someone who will take responsibility for doling them out.
Another thing that is sometimes done is to find a trustworthy person to entrust with secrets (e.g. your legal father isn't your biological father).
One way to handle such matters is to have a safe deposit box with this kind of stuff in it and to entrust to trustee to deliver these items at appropriate times.