The couple posted the news on their Stevens Nation Instagram account, writing that baby Stevens is due in January.
Eric Stevens' diagnosis with ALS, also known as Lou Gehrig's Disease, came just one month after marrying his wife, Amanda.
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There's currently no cure for ALS - and it almost always progresses, eventually taking away the ability to walk, speak and breathe. Most patients are given just 2-5 years life expectancy.
But despite the odds, Stevens has dedicated his life to helping others battle the disease.
Before firefighting, the Costa Mesa resident was a star athlete, competing at football's highest level. In college, he was captain for CAL Berkeley and signed by the then St. Louis Rams as an undrafted free agent in 2013.
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