abstract:The Court of Probate was created by the Court of Probate Act 1857, which transferred the jurisdiction of the ecclesiastical courts in testamentary matters to the new court so created.
The point of that example is that if a custodial parent refuses to execute Form 8332 in defiance of a probatecourt order, the noncustodial parent is still out of luck as far as the IRS and the Tax Court are concerned.
Moreover, insurance policies and IRAs made payable to specific beneficiaries (as opposed to your estate) and bank or investment accounts made payable on death aren't part of your court administered "probate" estate.
Guardianships and conservatorships require annual reporting to the ProbateCourt, and sometimes specific ProbateCourt authority for acts such as terminating medical care or sale of real property.