Nikki's fiancé, Artem Chigvintsev, sent his well-wishes on Instagram.
"Our Mama Bella, our Gigi, our Gato is about to head into brain surgery," Nikki wrote alongside sweet pics of her family. "I ask for so many prayers, so much light and love sent her way. Sadly they found what you can compare to a tumor on her brain stem that has been paralyzing her face."
"I have faith that the amazing doctors will do an incredible job and our Gigi will be on the road to recovery starting late today," she continued. "She’s loved by so many of us and just pray that her road to recovery is exactly what we are hoping for so we can put two new grand babies in her arms soon. Love you SOOO much Mom! You have a big Bella Army out here praying for you!!"
In the comment section, Gavin Rossdale wished Kathy a "speedy recovery," while Maria Shriver wrote that she's "sending you strength, sending you faith. We are here for you and [your] mama."
For Brie's post, she shared a photo of 3-year-old daughter, Birdie, with Kathy.
"Today my mom goes in for brain surgery. They realized she doesn’t have Bells Palsey but a mass on her brain stem," Brie wrote. "Couldn’t sleep because I was praying all night. She’s a strong one and I know all her angels will be with her. #BellaArmy send Mama Bella all the prayers and love today. Love you Mom @kathylaurinaitis"
"Sending you all the love and prayers," Jamie-Lynn Sigler commented.
"Wishing Kathy a lot of luck and speedy recovery, you’ll be back in no time sending you lots of prayers," he wrote alongside a pic of Kathy on his back and another of them dancing together.
Watch the video below for more on the Bella family.