After a hush-hush pregnancy, Amanda Seyfried and husband Thomas Sadoski finally welcomed their baby number two. 

In her recent Instagram post, the "Mean Girls" actress revealed that she just gave birth to a healthy baby boy.

Furthermore, the couple confirmed the surprising news in a statement released by two organizations -- International Network for Aid, Relief and Assistance (INARA) and War Child USA.

"Since the birth of our daughter 3 years ago our commitment to the innocent children that are so brutally affected by conflict and war has been a driving force in our lives. With the birth of our son, the work of INARA and War Child has become our North Star," Seyfried wrote on Instagram as she posted a photo of her baby while tagging the two organizations.

 
 View this post on Instagram
 @thomas_sadoski and I made a little man #Repost @thomas_sadoski ・・・ If you’re interested in helping out the (now) 4 of us would love it if everyone able could set up a monthly $4 (or $44!!) donation to BOTH of these incredible organizations that help make the world a better place for kids. Repost from @inaraorg & @warchildusa. We at War Child and INARA are so happy to be the first to announce that our board members Amanda Seyfried and Thomas Sadoski welcomed their second child into this world. ⁠ ⁠ Their statement:⁠ “Since the birth of our daughter 3 years ago our commitment to the innocent children that are so brutally affected by conflict and war has been a driving force in our lives. With the birth of our son the work of INARA and War Child has become our North Star.”⁠ @mingey @thomas_sadoski @inaraorg⁠ ⁠ ⁠#AmandaSeyfried #ThomasSadoski #BabyBorn #BabyAnnouncement #SecondChild #NewBorn #INARA #WarChild A post shared by  Amanda Seyfried (@mingey) on Sep 28, 2020 at 2:44pm PDT

 

The couple are both board members of INARA, which aims to provide "medical assistance to children impacted by war." At the same time, War Child USA empowers young people by giving them safe space through education programs and psychosocial support for the children affected by the battle.

Best known for his roles as Don Keefer in the political drama series "The Newsroom," Thomas Sadoski also took the opportunity to encourage the public to donate and participate in the charitable drive.

"If you're interested in helping out the (now) 4 of us would love it if everyone able could set up a monthly $4 (or $44!!) donation to BOTH of these incredible organizations that help make the world a better place for kids," the actor added.

Fans Are Baffled

Meanwhile, fans were baffled on how the pair managed to hide her pregnancy.

"How did you keep this a secret from the Seyfreaks so well?? I'm surprised none of us knew you were pregnant, but good job," one fan wrote.

Another user also praised Seyfried and the "Life in Pieces" actor for using their platform for a good cause: "Congratulations!! And so nice of you to use this announcement to ask attention to something so important Thank you. ️"

This is not the first time that the "Red Riding Hood" star and her husband kept things under the radar.

In 2017, the pair secretly tied the knot in Topanga, California. Weeks later, the 34-year-old actress gave birth to their daughter Nina, who is now three and a half years old.

Amanda previously explained to Porter magazine why they chose to have a low-key wedding instead of a lavish ceremony that is quite the norm in Hollywood.

"I get married all the time [on screen]. I was in a wedding dress last week," Seyfried shared. "I also go to premieres, where people take my picture. I just don't care about all that stuff."

At the time, the "Mama Mia" actress also spoke about motherhood and wanting "more babies." Seyfried said that she feels "more empowered" as she prioritizes her family over work.

"Like, I'll say no, I can't do that press trip, because I'm spending time with my daughter. 'Oh, you want my top off for that part? How about we scrap that sex scene altogether? And no, I'm not wearing those thongs!"

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