Reference

According to various sources, including Defense.gov, MMM-Online, and Los Angeles Times, a significant event in Montel Williams' life that happened in 1999 was his diagnosis with multiple sclerosis (MS).

In 1999, Williams was diagnosed with MS, a disease that affects the central nervous system. This diagnosis was a turning point in his life, as he had been experiencing symptoms for 20 years prior to the diagnosis. After the diagnosis, Williams established the Montel Williams MS Foundation to further the understanding and treatment of MS.

Here's an image of Montel Williams:

Image: Montel Williams by David Shankbone

It's worth noting that Williams has been open about his struggles with MS and has used his platform to raise awareness about the disease.