Kelly Clarkson’s estranged husband, Brandon Blackstock, filed a response to the singer’s divorce petition on Tuesday, July 21.According to the court documents obtained by The Blast, the 38-year-old American Idol alum and the 43-year-old manager are on the same page when it comes to the custody of their 5-year-old daughter, River, and 4-year-old son, Remington.