The Prez used his final day in office to grant pardons and commutations, and among the list of prisoners he commuted is Young ... who Kim began championing in 2018.

As you may recall ... Kim visited The White House in September 2018 -- a few months after Alice's release -- to continue to fight for criminal justice reform, and she lasered in on Young's case.

Much like Alice, Young was sentenced to life in prison without parole in 2014 for non-violent drug offenses -- weed and cocaine possession -- as part of Tennessee's 3 strikes law. He was just 22 at the time.

Sources close to the situation tell TMZ ... Kim stayed involved with Young's legal team since her WH meeting and continued to bring attention to the case. We're told Alice was also involved helping Chris -- they share the same attorney, Brittany Barnett.

The announcement from The White House says, "Mr. Young's many supporters describe him as an intelligent, positive person who takes full responsibility for his actions ..." While Kim was not mentioned among the several names of criminal justice reform advocates who assisted Young, her amplification of the case on social media certainly brought it much needed attention.

The statement says Young "lacked a meaningful first chance in life due to what another Federal judge called an "undeniably tragic childhood." adding the commutation gives Young a second chance.