The Judds’ story has all elements of a country music song — mom Naomi overcomes an impoverished childhood and single motherhood to become a chart-topping star along with elder daughter , then ends it all with suicide.

While their story is well known, this two-part documentary (the second part airs Sunday, May 11) also reveals secrets, like the childhood sexual abuse Naomi fought all her life to conceal and what actually led to her tragic death. The doc features interviews with Wynonna as well as Naomi’s actress daughter, , from whom she was estranged for years, Naomi’s widower, , and her close friend .