Article continues below advertisementKelly Clarkson is slowly stepping back into the spotlight one month after the passing of her ex-husband, Brandon Blackstock.On Thursday, September 4, the 43-year-old singer marked an emotional milestone on Instagram - celebrating more than two decades since she won American Idol in 2002.Article continues below advertisementSource: MEGAKelly Clarkson celebrated her 23rd 'American Idol' win anniversary.Article continues below advertisement"To everyone that took time 23 years ago to call in and vote for me, thank you 🙏," she began in her post's caption.