What practical experience does Pope Francis have with parenthood/fatherhood?

Recently I shared [Francis's tips for being a good father](https://aleteia.org/2015/03/20/pope-franciss-7-tips-for-being-a-good-father/) , but my atheist friends do not consider Pope as authority as I do and are asking what is pope's expertise with parenthood? By expertise I mean education or work with children, child psychologists, psychiatrists. I read [Wikipedia](https://en.wikipedia.org/wiki/Pope_Francis) but found nothing relevant. I also know about [Our Father](http://www.foxnews.com/opinion/2018/03/10/our-father-reflections-on-lords-prayer-by-pope-francis.html) book but it will not be strong evidence for Pope's experience by my friends. What I did for now was to explain that author is irrelevant and one should reason about content, not about author.