Father Eustáquio's time in Poá, São Paulo, is marked by several important events. One of them, dating from 1936, is the construction of the Grotto of Our Lady of Lourdes (a replica of the one located in France). It is from this place that news of the first miracles attributed to the religious figure's intercession originates. See what an excerpt from the book 'The Vicar of Poá', by Father Venâncio Hullselmans, recounts:

‘Among the enormous amount of luggage he brought back from his vacation in Holland, there was also a jug containing the precious liquid he so longed for: genuine Lourdes Water.
He waited until the new house was finished and the grotto was built to begin the campaign!
He poured half the jug into the tank behind the grotto, mixing the Lourdes Water with ordinary water (...)'’

‘'The people of Poá began a small pilgrimage, religiously seeking water from the tap at the grotto. It had to be miraculous water, because what Father Eustáquio said couldn't be a lie.'.
However, the effects of this Lourdes water were not very encouraging (…)'’

‘Finally, after two years of mixing, he himself had scruples about the authenticity of the water and, so as not to leave the people under the illusion that they were seeking miraculous water, he announced in the church that the Lourdes water had run out, but that he, personally, would bless the water in the tank so that they could continue to seek it, for it was holy water.
To his great astonishment, this water accomplished what the other had never been able to. It brought him a veritable pilgrimage, and not only in Poá, but throughout the surrounding area, the fame of the water spread as if it were miraculous.’