Carrie Underwood is glowing in a new Instagram photo she and husband Mike Fisher posted just two weeks after they welcomed their second child.

Earlier this week, Underwood took to Instagram to share a new photo of her and Fisher, along with a message about their newest cause. The couple wore matching black clothes and black hats in the first snap the country singer has shared since giving birth to second son, Jacob. They had their fists raised, and both had a red "x" on the back of their hand. 

In her caption. Underwood wrote that she and Fisher are joining the fight to end slavery that is still happening all over the world. "@mfisher1212 and I are #InItToEndIt to shine a light on modern day slavery... @enditmovement," she wrote.

The photo was originally posted on Fisher's Instagram page, where he also encouraged his followers to join him and his wife in "raising our voices to fight against modern day slavery."

Some netizens have criticized the couple for their cause, pointing out that the United States had more pressing issues than this. However, many of their Instagram followers also pledged to their cause and revealed that they have joined the movement.

"My 14 year old son just participated last Thursday, and he tells anyone we come across! Thank you guys for also being involved! #InItToEndIt," Instagram user loren_28_86 wrote on Underwood's post.

This new post comes after Underwood and Fisher welcomed their second children, Jacob Bryan Fisher, on Jan. 21, and shared the first photos of the newborn on Instagram. 

Underwood shared several photos of her, Fisher and their eldest son, Isaiah, holding the newborn on Jan. 24, along with a special message. In one snap, Fisher has a big smile on his face as he shows off his second son, while another picture featured Underwood cuddling with Jacob. Another sweet snap showed big brother Isaiah's first meeting with his younger brother.

"His mom, dad and big brother couldn’t be happier for God to trust them with taking care of this little miracle! Our hearts are full, our eyes are tired and our lives are forever changed. Life is good..." Underwood wrote in the Instagram post.

Prior to giving birth to Jacob, Underwood suffered three miscarriages over the last two years. 

Carrie Underwood, Mike Fisher Carrie Underwood shared a new photo two weeks after giving birth. Pictured: Mike Fisher (L) and Carrie Underwood attend the 2018 CMT Music Awards at Bridgestone Arena on June 6, 2018 in Nashville, Tennessee. Photo: Getty Images/Rick Diamond