Taking to Twitter, new dad JB Gill revealed that wife Chloe had given birth to the couple's first child on Friday 19th September.
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He wrote proudly: "A little nose,lots of hair and looking like his mummy @ChloeSGill our baby boy was born 19/09/14 weighing 6lb15"
Wife Chloe added: "I'm so blessed to have a little miracle in my arms. Thanku @JBGill - couldn't have done it without you.
"I'm so in love with my boys"
JB's JLS bandmates (aka the bubba's brand-new surrogate uncles) were quick to offer their congratulations.
Marvin Humes, who is father to daughter Alaia Mai, wrote: "Had the pleasure of meeting @JBGill and @ChloeSGill beautiful baby boy..so proud of you both! God Bless you all x"
His wife Rochelle added: "He is such a beautiful boy, he gave me the bestest cuddle. Didn't wanna hand him back over #ilovehim Proud of u both"
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Bandmate Aston Merrygold, who just signed a record contract as a solo artist, wrote: "Proud uncle"
And, while bandmate Oritsé has yet to write a message, his partner Aimee Jade who recently gave birth to the couple's son Omré - made sure to send her well wishes to JB Gill and Chloe.
She wrote: "Congrats guys. Great news, welcome to the world baby Gill! Omré's friend has come to join him... Double Trouble lol xx"
No word on what the little boy is called yet, but we will keep you updated as and when we find out.
Congratulations to the happy couple!