The McBusted singer is thrilled his bandmate and wife Izzy are expecting their first child, and joked the baby will grow up to either be very close to or an ''arch enemy'' of his own son, 16-month-old Buzz.
Tom - who is married to author Giovanna Fletcher - tweeted: ''Massive congrats to @mcflyharry and @izzyeyesalight for growing Buzz a bandmate/wife/husband/BFF/arch enemy. Whoop whoop!!! (sic)''
And fellow McBusted star Danny Jones is equally delighted by the news.
He posted: ''#BabyJudd well done @mcflyharry & @izzyeyesalight super duper news!!!(sic)''
Harry and Izzy shared their happy news earlier today (22.07.15) and have been inundated with messages of congratulations from fans.
Thanking well-wishers for their support, the 28-year-old musician admitted he ''can't wait'' to be a dad.
He wrote: ''Thanks for all of your sweet messages. @izzyeyesalight is going to be an incredible Mum and I can't wait to be a Dad! #babyjudd (sic)''
Harry and Izzy - who was the violinist in classical group Escala - met when she performed as part of the string section on McFly's 2005 tour.
The couple got engaged in May 2012 during a romantic getaway in St. Lucia and they got married in December that same year.
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