My best high school friend had an uncle, his father's brother, who had achieved a prestigious position in the church hierarchy. My friend war formally an atheist, a member of the communist youth organization (and later party member and even candidate for the senate from our province.) We both attended Milan's public university. As soon as he graduated, he miraculously got a paid position as research assistant in the department of contemporary history at Milan's CATHOLIC University (The Sacred Heart.)
How? I didn't need to ask.
Not only. In those days military service in Italy was still mandatory, 50 weeks or something like that. It was common to get student deferrals until we completed our degrees. One day he told me that his uncle had called him out of the blue and told him to go to the local military recruitment office to pick up his discharge papers. Just like that. All our other friends, yours truly included, did our 50-week stint.
A couple of years earlier, my sister, after finishing high school, decided she wanted to get a physical education degree. She was a top gymnast in Italy. The most convenient school, distance wise, was the Catholic University of Milan. But it wasn't easy to get in. Good grades etc. did not suffice. It was necessary to get a push. Since we didn't grow up Catholic, we didn't know anyone directly who could give her the push. So I mentioned it to my friend. Actually I asked point-blank. No problem: he called his uncle, his uncle wrote a letter to the admissions office, and my sister got in.
So, nepotism, favors etc. BUT, the clergy has no power to promote a family member or a friend INSIDE the clergy itself. Even if my friend had become a priest, his uncle would not have been able to help him in any way climbing the hierarchy ladder. The clergy's influence extends into civil society, but inside the church the only criterion for advancement is meritocracy.
One additional fact. The church will accept into the priesthood only men in excellent health. You will never see a priest with a birth disability of any kind. One may feel the call, beg and cry to become a priest, but if HE is not in top shape, no chance. The official reason? It's a tough job, requires a lot of stamina, and in order for one to devote himself completely to the church and the needs of the believers, one must have the necessary physical and psychological strength.
And the call from God? Answer: "There are many other ways to serve Him". Women are very familiar with this answer.
(Dozens of other similar anecdotes upon request).
PBS Frontline 2014 Secrets of the Vatican https://youtu.be/q7mmL1djtcY
Holy Money - Vatican City Corruption - (CBC News - Canadian Broadcasting Corp.)
https://youtu.be/EPdEJZ3IH8Y