The Manchester United star was expecting twins with his partner Georgina Rodriguez. The couple revealed she gave birth to a girl, however, their son has passed away.
"It is with our deepest sadness we have to announce that our baby boy has passed away," Ronaldo began his statement.
"It is the greatest pain that any parent can feel.
"Only the birth of our baby girl gives us the strength to live this moment with some hope and happiness.
"We would like to thank the doctors and nurses for all their expert care and support. We are all devastated at this loss and we kindly ask for privacy at this very difficult time."
"Our baby boy, you are our angel. We will always love you."
In October, the Manchester United forward revealed that he is expecting twins with Georgina.
Georgina revealed in December 2021 the twins she is expecting were going to be a boy and a girl.
Ronaldo shares daughter Alana, four, with Georgina and also has a son Cristiano Jnr, 11, as well as twins Eva and Mateo, four, via surrogate mothers.
Responding to Ronaldo's announcement, Manchester United said: "Your pain is our pain, @Cristiano [heartbreak emoji].
"Sending love and strength to you and the family at this time."
It's not clear whether Ronaldo will play any part of Manchester United's Premier League clash against Liverpool on Tuesday night.