The 32-year-old let slip Tom's happy news during an appearance on ITV's Lorraine on Tuesday morning.
While Tom and Kelsey have yet to publicly announce the news, Max couldn't help but share his friend's joy during an update on his health after Tom revealed this month that he has been diagnosed with an inoperable brain tumour.
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"Kelsey gave birth to their second child last week. He’s a fighter Tom, Tom will be alright. If he’s watching by the way, I love you all."
Max George shared Tom's happy news on ITV's Lorraine
Earlier this month, Tom made the heartbreaking announcement on Instagram, sharing a family photo of himself and Kelsey with their 16-month-old daughter Aurelia.
He wrote: "Hey guys, you know that we've both been quiet on social media for a few weeks and it's time to tell you why. There's no easy way to say this but I've sadly been diagnosed with a Brain Tumour and I'm already undergoing treatment.
Tom shared a family photo on Instagram as he shared his diagnosis
"We decided, after a lot of thought, that rather than hiding away and trying to keep it a secret, we would do one interview where we could lay out all the details and let everyone know the facts in our own way.
"We are all absolutely devastated but we are gonna fight this all the way. We don't want your sadness, we just want love and positivity and together we will raise awareness of this terrible disease and look for all available treatment options.
"It's gonna be a tough battle but with everyone's love and support, we are going to beat this. Tom and Kelsey xxx."
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