Estate tax return

My wife is the fiduciary for her decedent mom's estate, which holds a couple of houses in the US and has 4 beneficiaries, the 4 children.  One of those houses was sold in 2021 and there were long term capital gains (she died in 2019).  I filed (and mailed to the IRS) K-1 forms for each beneficiary indicating each of their share of the gain, and also mailed each beneficiary a copy of their K-1.  I did not file a 1041 for the estate - yet.  Do I need to file a 2021 tax return (1041) for the estate?  

 

When I did our family's taxes (using TurboTax Deluxe) I reported that I received a K-1 and the amount was included on my Schedule D.  I did not attached it to my return, however.  I did attach it to the state return, though.

 

Obviously I'm confused.  We probably should've hired a tax guy but we didn't realize the house sale would affect our taxes, nor did we understand all the ramifications of being the fiduciary of the estate.  Should I be purchasing TurboTax Business to do an estate return?  Seems pricey for the circumstances of the estate.  Thanks for any help!