She was also instrumental in encouraging Alphonsus Liguori to found the Congregation of the Most Holy Redeemer (Redemptorists), a missionary order of priests and brothers.

She was the tenth of twelve children born to Francesco Crostarosa and Paola Battistini Caldari;[2] descended from the Lords of Abruzzo and Aquila.

[3] While there, she met Father Thomas Falcoia of the Pious Workers, who served as her spiritual director following the death of Cacace.

She remained in the convent for under a decade and in 1724 relocated along with her sister to enter a religious conservatory founded by Falcoia in Scala, high above the Bay of Amalfi.

[5] Her first recorded vision of Jesus Christ was on 25 April 1725 when she was still a novice, seeing him "...in a wonderfully pure light... with an inexpressible jubilation of love...

Crostarosa had support from some of her fellow nuns during this time, but she also faced punitive measures from superiors, such as being forbidden from taking communion for a few weeks, being exiled to the convent's attic, or having to eat meals sitting on the floor with a rope around her neck.

[6] As it happened, Bishop Guerriero had invited the young Alphonsus Liguori, a friend of Falcoia, to give a retreat to the nuns at Scala.

With Guerrierro's approval, and the unanimous consent of the nuns, the convent would switch to rule of life from Crostarosa's vision on the following Pentecost, 31 May 1731.

The much-higher number of priests in large cities at the time meant that the rural poor received comparatively little benefit from the ministries of the Church.

Liguori consulted many other advisors and friends about it, including Falcoia, but Crostarosa's words imparted special urgency, and he ultimately trusted her visions.

Sister Crostarosa was distressed at the thought of asking God to inspire her to again; nevertheless, she had a vision one night soon after of Jesus comforting her, and in the morning she wrote down a new copy of the rule.

Liguori was inclined to defer to Falcoia for the sake of canonical obedience, and he chided Sister Crostarosa to do the same; this damaged their friendship rather than persuade her.

Around March 1733, when it became clear that Crostarosa would continue to resist his leadership, Falcoia told Liguori to bring the nuns back in line.

Falcoia gave her a set of ultimatums[note 1], threatening to expell her from the convent, and Crostarosa refused, particularly being no longer able to trust him as a spiritual director.

[9] Pope Francis approved the findings of the Congregation for the Causes of Saints and proclaimed her to be Venerable on 3 June 2013 on the account of her heroic virtues.