United Kingdom, April 23 -- Christina Applegate has been a "guiding light" for Chad King as he lives with multiple sclerosis (MS).

The 54-year-old actress and the A Great Big World member, 40, were diagnosed with the incurable chronic autoimmune disease that impacts the brain and spinal cord in 2021 and 2007, respectively, and Christina's openness about living with MS has given comfort and strength to Chad.

The Say Something hitmaker told People: "Christina Applegate has been a guiding light for me in this whole process, which has been amazing.

"Every person with MS has different symptoms. It varies completely. Christina has different symptoms than me, and it's like we're going through our own struggles, but we can come together. She l...