The parable begins with a man who had two sons, and the younger of them asks his father to give him his share of the estate. The implication is the son could not wait for his father’s death for his inheritance, he wanted it immediately. The father agrees and divides his estate between both sons.
Upon receiving his portion of the inheritance, the younger son travels to a distant country and wastes all his money in extravagant living. Immediately thereafter, a famine strikes the land; he becomes desperately poor and is forced to take work as a swineherd. (This, too, would have been abhorrent to Jesus’ Jewish audience, who considered swine unclean animals.) When he reaches the point of envying the food of the pigs he is watching, he finally comes to his senses:.

And when he came to himself, he said, How many hired servants of my father’s have bread enough and to spare, and I perish with hunger! I will arise and go to my father, and will say unto him, Father, I have sinned against heaven, and before thee, and am no more worthy to be called thy son: make me as one of thy hired servants. And he arose, and came to his father. But when he was yet a great way off, his father saw him, and had compassion, and ran, and fell on his neck, and kissed him.
— Luke 15:17–20, KJV

This implies the father was hopefully watching for the son’s return.
In most versions of Luke, the son does not even have time to finish his rehearsed speech, before his father accepts him back wholeheartedly without hesitation[5] as the father calls for his servants to dress him in a fine robe, a ring, and sandals, and slaughter the “fatted calf” for a celebratory meal.
The older son, who was at work in the fields, hears the sound of celebration, and is told about the return of his younger brother. He is not impressed, and becomes angry. He also has a speech for his father:

And he answering said to his father, Lo, these many years do I serve thee, neither transgressed I at any time thy commandment: and yet thou never gavest me a kid, that I might make merry with my friends: but as soon as this thy son was come, which hath devoured thy living with harlots, thou hast killed for him the fatted calf.
— Luke 15:29–30, KJV

The parable concludes with the father explaining that because the younger son had returned, in a sense, from the dead, celebration was necessary:

It was meet that we should make merry, and be glad: for this thy brother was dead, and is alive again; and was lost, and is found.
— Luke 15:32, KJV

Source: https://en.wikipedia.org/wiki/Parable_of_the_Prodigal_Son#:~:text=The%20Parable%20of%20the%20Prodigal,disciples%2C%20the%20Pharisees%20and%20others.