My tax client's spouse died in 2018 (age 75) and the plan administrator failed to issue his RMD for 2018 to the surviving spouse.  The error wasn't caught until 2019, when they made the distribution.  I know I need to file form 5329, but do I (1)prepare an amended return for 2018 with that form (2) just prepare form 5329 for 2018 and mail it with the waiver request or (3) somehow include this with her 2019 return? Any help would be greatly appreciated.