I also suggest that you read IRS Pub 559 (Survivors, Executors, and Administrators) for a lot of good information about filing the final return and estate return and other requirements.
https://www.irs.gov/pub/irs-pdf/p559.pdf
If he is married then his surviving spouse can file a joint return in the year of death. If the spouse is the benificuary of the IRA then a spouse can choose to roll the inherited IRA into their own IRA.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
