It all started when Junior's dad Peter Andre posted a cute family video of himself playing an egg catching game with daughter Princess, as Junior danced in the background.
Someone commented on the post: "Junior is always bopping around, so funny!"
However, they added: "Nice to see what real families do and not what Katie does, which is use her kids to make the headlines! Sorry but had to be said."
Clearly keen to stick up for his mum, Junior – who is just 14 years old – replied to the troll who criticised his mum's parenting skills.
Nice to see what real families do and not what Katie does, which is use her kids to make the headlines! Sorry but had to be said.
He said: "You don't need to post negative stuff about my mum."
Peter was clearly keen to stop things escalating and turned off the comments on his post.
Letting his eldest kids have social media accounts has long been a worry for Pete.
Recently someone impersonated Junior on Instagram and asked their followers to send him inappropriate pictures.
Pete told New!: "I found it very worrying that someone set up an Instagram account posing as Junior and asked people to send inappropriate pictures, but I'm so proud of the way my son handled it."
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Katie, meanwhile, is on a mission to make online trolling a crime with the introduction of Harvey's Law.
She recently begged fans to "name and shame" the troll who had called her disabled son "fat".
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