Complex sentence: Lujan grew up in Littleton, Colorado before joining the United States Marine Corps in 1993 and was honorable discharged in 1997, where he returned to Colorado to become more active in parenting his young daughter Emily.
Split into simpler sentences: Lujan grew up in Littleton Colorado before joining the Marine Corps in 1993. He served honorably until his discharge in 1997, where he returned to Colorado to become more active in parenting his young daughter Emily.