As is the case with many films, television episodes, and literature, title of this episode misuses the word prodigal. The Christian parable of the prodigal son uses the term, not because the son left and returned home, but because he was wasteful. The term prodigal refers to one who wastes money or resources freely and recklessly.
The title of the episode is a reference to the Biblical parable known as the "Prodigal Son". However, the Prodigal Son wasted all his money and came home penniless. In contrast, Ezri comes home as a commissioned officer on a promising career path.
Kevin Rahm guest-stars here as Ezri Dax's brother Norvo Tegan. He would later go on to have a recurring role in the TV series Lethal Weapon (2016) as Police Captain Brooks Avery, who's name interesting enough was based off the name of Avery Brooks, who plays Captain Benjamin Sisko in the series.