Kelly Clarkson and Brandon Blackstock's "changed their perspectives" amid his cancer battle

The insider told Us Weekly: "Co-parenting was not easy for Kelly because she was the one who had to transport the kids, so it was really her life that was always turned upside down."

Despite this, Kelly - who had River, 11, and Remington, nine, with Brandon - was always determined that the kids "were with their dad and his family as much as possible".

The source added: "She made a lot of concessions to make that happen. They have had a bunch of family events in the past months that she allowed her kids to be present for.

"They were out there [in Montana] visiting him, and I know she let them miss school a bunch to attend a family wedding and Reba [McEntire's] rodeo concert, as well as some other things that the entire family did together. She felt it was important."

Brandon's death was announced on Thursday, with a rep telling People that he was "surrounded by family" when he passed away.

The statement read: "It is with great sadness that we share the news that Brandon Blackstock has passed away.

"Brandon bravely battled cancer for more than three years. He passed away peacefully and was surrounded by family.

"We thank you for your thoughts and prayers and ask everyone to respect the family's privacy during this very difficult time."

Brandon's passing was announced shortly after Kelly postponed her Las Vegas residency in order to spend more time with their children.

The 43-year-old pop star - who was married to Brandon between 2013 and 2022 - wrote on X: "Unfortunately, I need to postpone the remainder of the August Studio Session dates in Las Vegas.

"While I normally keep my personal life private, this past year, my children's father has been ill and at this moment, I need to be fully present for them."

The pop star revealed at the time that Brandon was ill, although she didn't share any other details about his sickness.

Her post added: "I am sincerely sorry to everyone who bought tickets to the shows and I so appreciate your grace, kindness and understanding."