Already Thinking About Baby No. 2? Joaquin Phoenix & Rooney Mara See Parenthood As The 'Best Thing That's Ever Happened To Them,' Says Source

It’s only been six months since Rooney Mara and Joaquin Phoenix quietly welcomed their first child, but a friend says the blissed-out couple is already thinking about growing their family. 

Mara, 35, and Phoenix, 46, who were spotted out and about with their baby boy, River, in L.A. on February 26, “both knew becoming parents would be great, but they say it’s the best thing that’s ever happened to them, especially Joaquin,” the pal spills to OK!, adding that having this little family has "exceeded all their expectations."

The couple named their son after the Joker star’s late brother, who tragically died of a drug overdose in 1993 at the age of 23. “It’s been healing for Joaquin in a way he could never have imagined,” shares the friend. 

Phoenix had opened up about River's legacy in an interview with Anderson Cooper, saying that he always felt his presence in his work.

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"I feel like in virtually every movie that I made, there was a connection to River in some way. And I think that we've all felt his presence and guidance in our lives in numerous ways," he said.

Mara and the Oscar winner — who hooked up in 2016 and confirmed their engagement three years later — “would love to have another child soon so River will have a sibling close in age,” the pal adds. “There are whispers they hope to be pregnant again by spring or summer!”

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Currently, the two are living in the Hollywood Hills neighborhood, along with their two dogs named Oskar and Soda, and tend to stay out of the public eye. 

“They don’t really like to go out,” an insider told Us of the private pair. “They mainly just like to be with each other as the two of them. They’re in their own bubble.”