Cristiano Ronaldo's eldest son, Cristiano Ronaldo Júnior, made his debut for Portugal under-15s on Tuesday in a 4-1 win against Japan.
With Portugal leading 3-0 thanks to a hat trick from Braga's Rafael Cabral, Ronaldo Júnior came on in the 54th minute of the encounter.
"Congratulations on your Portugal, debut, son. Very proud of you," Ronaldo wrote of his son in a post on social media.
Ronaldo Júnior, 14, plays as a forward for Al Nassr's academy.
Tuesday's game was the first of four that Portugal's U15 squad will play in Croatia as part of the Vlatko Markovic international tournament.
Portugal take on Greece on Wednesday, before facing England on Friday.
They end the tournament on Sunday against an opponent yet to be determined.
