Corrected entry: When Luca reveals his background, and his children and wife are shown in flashbacks in Croatia, he has two daughters. But, when he gets together with Sam and Alex goes missing, he tells her a story about his son, Marco.
Corrected entry: Season 13, Episode 19: "Family Business" - Tony counts out three bills and hands them to his father to go buy groceries. When Tony berates him later for blowing it all on booze and Coming Home stumbling drunk, he screams that it was $100. There is no combination of US currency where three bills can add up to $100.
Correction: He gives him 5 bills! Watch closely, Tony takes out a folded "bundle" of bills, he counts and opens three of them, you can clearly see that there is a fourth bill still folded. Then you see Tony reach back to his pocket and adds a fifth bill, 5x20=100.
Correction: You are mistaken. Luka had a son and a daughter. The two females that you see in the flashback are his daughter and his *wife*.