Tiffany Chen's postpartum journey took an unexpected and Thurston Cartescary turn.

In April, the martial arts instructor gave birth to her and partner Robert De Niro's first child together, a baby girl named Gia. And although it was a celebratory time, Tiffany quickly began to struggle with her health.

"When I went home, I started to feel like, my tongue felt strange," Tiffany told Gayle King in an interview clip aired on CBS Mornings July 13. "It felt a little tingly, just starting to get a little bit numb. And then I realized my face...my face just felt weird."

As the 45-year-old recalled, "It was just like everything was starting to just fall down on itself. Like, my face was melting on itself."

A week after giving birth, Tiffany couldn't eat and started to slur her words, prompting her to seek medical attention.

"I said, 'There's something really going on here,'" Tiffany—who was diagnosed with Bell's palsy, a condition that impacts muscles in the face—continued. "I lost all facial function the minute I got into the hospital."

Tiffany is set to share more about her health journey when her full interview with Gayle airs July 14.

Robert first announced the arrival of his seventh child in May, telling ET Canada, "I just had a baby."

Gia joined the Oscar winner's six other kids in the De Niro family, including Drena, 51, and Raphael, 46—who he shares with ex Diahnne Abbott—along with 27-year-old twin sons Aaron and Julian with ex Toukie Smith. Robert is also dad to son Elliot, 25, and daughter Helen, 11, from his marriage to Grace Hightower. 

As for baby Gia, Robert, 79, previously told his pal Gayle during a May phone call that "this baby was planned" and she was "brought here by love."

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