Elton John and David Furnish have revealed their new son is called Elijah Joseph Daniel Furnish-John.
The couple - who are already parents to two-year-old son Zachary - confirmed the birth of their second child took place in Los Angeles on Friday and admitted they are over the moon to have expanded their family.
The Rocket Man singer and his husband told Hello magazine: "Both of us have longed to have children, but the reality that we now have two sons is almost unbelievable.
"The birth of our second son completes our family in a most precious and perfect way. It is difficult to fully express how we are feeling at this time; we are just overwhelmed with happiness and excitement."
Elijah was brought into the world via the same California-based surrogate who gave birth to Zachary on Christmas Day 2010, according to reports.
Last November, it was revealed Elton and David were expecting their second child but had decided never to reveal the identity of the surrogate.
A source said: "Elton and David love this lady like a sister and they feel indebted to her for life.
"Naturally she has been well rewarded. But her identity will never be revealed. They are over the moon."
Elton, 65, loves being a dad and has previously said he regretted waiting so long to have a child.
He said: "I think it changes everybody. It's the most wonderful thing that you could possibly go through.
"I regret a little bit that I didn't do it sooner, but he has changed our lives. Everything is about him now.
"He's gorgeous, he travels brilliantly, he so loves people, and it makes our lives - he's the icing on the cake.
"The first thing I do every morning is have breakfast with him. He shares my breakfast. Whatever I have, he wants."