The doting dad, who shares Jett, seven, and Bunny, six, with the former glamour model, 42, isn’t happy that he wasn’t even told about the dramatic change before it happened.
Jett used to have a lovely mop of curly hair, but now it’s all gone and Kieran, 33, took to his Instagram account to share a video of Jett showing off his new locks
He said in the video: “Oh my god, where’s your hair gone? You’ve come back from mummy’s with no curls!
“Where’s all my curls gone?”
“Santa took it,” Jett told his dad.
“Oh my baby boy’s growing up,” Kieran went on. “Genuinely though I am sad, look how short your hair is, I miss your curls.
“Don’t you like your curls?”
Jett said: “Ask Santa because he might fix it.”
Katie’s rep declined to comment when contacted by Mirror Online.
Kieran hasn’t always seen eye-to-eye with Katie since their split..
The former stripper, who is now dating Michelle Pentecost, says he’s happier than ever after finding love once more.
The couple, who met because their children attend the same school, are engaged and looking to their future together.
Marking her birthday earlier this month, Kieran shared a string of loved-up snaps of them together and wrote: “Happy birthday to my beautiful fiancée. Michelle you have come into my life and made me the happiest man alive.
“I know your lockdown birthday won’t be exactly as we might have planned but trust me it’s going to be a good one. Your a great role model for my children, and I love our little family. Let’s celebrate the proper way in lockdown just me, you and the kids!!!! Games, food and lots of laughs. We all love you so much and life wouldn’t be the same without you in it.”
Kieran and Michelle, who also has a son, regularly posts sweet snaps of their blended family having fun hanging out together.
Last month, Kieran shared a cute Halloween-themed picture and penned: ” Michelle and I live for our children and We love the time we spend together. Moments we will cherish forever, memories that will last a lifetime.”