Who gets refund of deceased taxpayer? I am completing my mom's final income tax return (up to the time of death). She is due a refund. Should that go into her estate?

The refund for a deceased taxpayer would go to the estate.  Once the estate is closed any remaining funds would be distributed to the next of kin.  

Per the IRS, if the estate has to file a return, "A deceased person's estate figures its gross income in much the same manner as an individual. See the definition of adjusted gross income. Most deductions and credits allowed to individuals are also allowed to estates and trusts. However, a trust or an estate may also have an income distribution deduction for distributions to beneficiaries.

Report income distributions to beneficiaries and to the IRS on Schedule K-1 (Form 1041).

• For calendar year estates and trusts, file Form 1041 and Schedule(s) K-1 on or before April 15 of the following year.
• For fiscal year estates and trusts, file Form 1041 by the 15th day of the 4th month following the close of the tax year."

See the link below for more information:

• Filing an estate tax return