Query on LTCG in the hand of legal heir

The property (land and constructed house on it) was sold in p.y 2018-19. The assessee passed away in February 2019. Will the ltcg on the sale be taxable in the hands of legal heir? 

Will any notice under section 147,156,270a to the deceassd be a valid notice in 2023-24?

* the department was not informed of the death

* ITR wasn't filed for AY 2019-20