Ex-Kansas City Chiefs assistant coach Britt Reid -- Andy's son -- just had his three-year prison sentence commuted to house arrest. Missouri Governor Mike Parson made the surprising decision on Friday ... a little over a year after Reid was thrown behind bars for his role in a DWI crash that left a 5-year-old girl, Ariel Young, with life-altering brain injuries. A spokesperson for Parson explained the move in a statement to media outlets ... saying, "Reid had completed his alcohol abuse treatment program and has served more prison time than most individuals convicted of similar offenses." As part of his commutation, Reid will remain on house arrest until October 31, 2025. He'll have to abide by a lengthy list of conditions in order to avoid being thrown back in prison, however -- including working at least 30 hours a week, submitting to random drug screenings, and completing at least 10 hours a month of community service. Reid is also forbidden from making contact with Young or her family members. Reid was first hit with criminal charges in the case after authorities said he got drunk days before the Chiefs vs. Buccaneers Super Bowl in 2021 and slammed his pickup truck into the back of a car Young had been riding in. Authorities alleged Reid was going 83.9 MPH in a 65 MPH zone just before the wreck, and had a BAC of .113 two hours following the accident. Dash cam footage captured at the scene showed Reid was wearing a Chiefs COVID mask and a Chiefs sweatshirt in the minutes after the crash. Reid lost his job with Kansas City's NFL franchise a short time later ... and didn't work in the league again before beginning his sentence in November 2022. We've reached out to an attorney for the Young family for comment, but so far, we haven't heard back yet.