Is an inherited distribution of an annuity payment taxable

[lrubin28]

My wife received a 1099R from Equitable Financial Life - she received this money after her mother died last year.  The distr code is 4D, so it's some sort of annuity payment.  
I thought inherited money is not taxable?  Although know a 1099R is taxable...I'm confused!

[dmertz]

What your wife inherited is Income in Respect of a Decedent (IRD).  It's taxable income the same as it would have been taxable income if it was paid to your wife's mother before she died.