Christina Applegate observes 50th birthday amid MS battle: 'It’s been a hard one'

Christina Applegate marked a milestone birthday. 

The "Dead to Me" star, who first broke through on Fox's comedy "Married ... With Children" in the late '80s, commemorated the occasion in a special tweet to her nearly 1.5 million followers Thursday. 

"Yup. I turned 50 today," she wrote. "And I have MS (Multiple sclerosis). It’s been a hard one. Sending so much love to all of you this day.

"Many are hurting today, and I am thinking of you. May we find that strength to lift our heads up. Mine currently is on my pillow. But I try."

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The Emmy winner went public with her MS diagnosis in August, which she told her Twitter followers she'd received "a few months" earlier. With MS, the body's immune system begins attacking the central nervous system, according to the National Multiple Sclerosis Society, triggering various neurological symptoms.

"It’s been a strange journey," Applegate wrote in August. "But I have been so supported by people that I know who also have this condition."

Applegate's "The Sweetest Thing" co-star Selma Blair, who also has MS, responded with a message of support. "Loving you always," the "Cruel Intentions" star tweeted. "Always here. As are our kids. Beating us up with love"

In the weeks that followed, Applegate has continued to post about her illness. 

"Happy national dance day. My little MS FEET still work," she tweeted Sept. 18, pointing and flexing her foot. Last month, she posted about the television shows she has watched during "days of being in bed" ("Only Murders in the Building" and "Dancing With the Stars.")

"Being technically disabled is what it is," Applegate tweeted Oct. 27 in a message promoting Blair's documentary chronicling her stem cell transplant to treat the disease. "I didn’t know what MS was before I had it. My life is changed forever."

The actress has spoken out about health struggles in 2008, when she was diagnosed with breast cancer and had a double mastectomy. In 2017, Applegate revealed she had had her ovaries and fallopian tubes removed. 

"My cousin passed away from ovarian cancer in 2008. I could prevent that," she told the "Today" show. "That’s how I’ve taken control of everything. It’s a relief. That’s one other thing off the table. Now, let’s hope I don’t get hit by a bus."

Contributing: Hannah Yasharoff