How to Get Away with Murder's Karla Souza Tandem Nurses Daughter, 2, and Newborn Son

Karla Souza is a multitasking mama!

The How to Get Away with Murder alum showed off her skills as a new mother of two on Instagram Friday, posting a black-and-white snapshot of herself tandem breastfeeding her newborn son Luka Olivares, 3 weeks, and daughter Gianna, 2, while sporting a giant, open-mouthed smile.

"This pic was taken the day after I gave birth," wrote Souza, 34, in the caption. "I'm laughing from both the joy and the excruciating pain of childbirth and postpartum."

The actress called delivering her son "THE most difficult and painful thing my body has had to go through," but admitted, "it has also made me feel like a freakin' warrior ... ALL women are warriors!"

"Now here I am, double nursing (not something I was planning on doing), to the sounds of beautiful diaper music 💩," she joked.

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Souza went on to say that motherhood "requires next-level strength and endurance," thanking those "who have helped carry me through this process!"

"And to all the mom's out there, know that I see you and honor you! #StrongLikeAMother," the Mexican actress concluded, before writing out the same caption in Spanish.

Souza and her husband Marshall Trenkmann welcomed baby Luka to their family on Friday, June 12, her manager confirmed to PEOPLE the following week. He was born in Los Angeles, weighing 7 lbs., 4 oz.

"Luka was welcomed at home by his 2-year-old big sister Gianna who is already busy teaching him the words to 'Poco Loco' from Coco," Souza said.

RELATED VIDEO: How to Get Away with Murder's Karla Souza Gives Birth to First Child: "Welcome Baby Girl Gianna"

The El Presidente actress, who married Trenkmann in 2014, announced her pregnancy in May, showing off her baby bump in a snapshot she posted to Instagram.

For the sweet photo op, the second-time mom-to-be was dressed in a pink "Mama Bird" T-shirt while holding Gianna, who was wearing a matching "Little Bird" shirt.

"Those of you who have already watched module one of #Unleashed already know this, but building this course has also coincided with my pregnancy ❤️," Souza wrote in the caption, referring to her online self course.

"Opening up in such a deep way while creating life has been such a gift and I'm honored to continue sharing, growing, and UNLEASHING with you all over the course of the next four weeks," she added.