The McBusted singer announced the exciting arrival of his daughter, Lola Rose Emma, on Twitter on Tuesday morning (26 January) with a heartfelt message.
Clearly bursting with pride, Harry couldn't help but gush about his "girls" while heaping praise on new mum Izzy.
He said: "Both Mummy and Lola are doing very well. Izzy is my hero and I love my girls." How cute is that?
Harry revealed Izzy gave birth the night before the announcement, at 8:43pm on 25 January.
Lola Rose Emma Judd entered the world at 8:43pm 25/1/16. Both Mummy and Lola are doing very well. Izzy is my hero and I love my girls— Harry Judd (@mcflyharry) January 26, 2016
They couple first announced they were expecting a baby back in July 2015 when the Strictly Come Dancing champion revealed: "Izzy and I are so happy and feel truly blessed to be able to share with you that we are expecting our very own little miracle #BabyJudd."
A short while after, Harry revealed in an interview that they conceived with the help of IVF, and kept fans updated with important milestones throughout the pregnancy - including the first time he felt the baby kick.
The new parents have been together for 10 years, after meeting when former Escala violinist Izzy joined McFly's 2005 concert tour. They tied the knot in December 2012.
Marking 10 years together, Harry wrote: "10 years ago today @izzyintheattic and I shared our first kiss on the Wonderland tour in Cardiff. A whole decade of laughter, love and happiness. Love you Iz xxx."
Izzy, in turn, said: "10 years ago tonight I shared my first kiss with @juddymcfly Thank you for filling my life with love, laughter and happiness, you are my everything xxx."
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