David Beckham is ''so proud'' of his younger sister after she gave birth for the first time.

The former footballer took to his Instagram account to share a picture of himself with his niece Peggy, and praised his sibling Joanne Beckham for having such a ''beautiful family''.

David wrote on Instagram: ''Welcome to the world little Peggy So proud of my little sis and congrats @krissydonners #Daddy such a beautiful family #proudUncle @joannebeckham (sic)''

The 42-year-old star - who has four kids of his own, Brooklyn, 18, Romeo, 15, Cruz, 12, and six-year-old Harper, with wife Victoria Beckham - shared two pictures of himself with the tot, and another of Peggy's pink cuddly teddy bear toy.

In one snap he is seen with a huge grin on his face while holding the youngster.

Joanne and her 'Big Brother' star boyfriend Kris Donnelly welcomed their daughter into the world on Saturday (09.12.17), and she praised the reality TV star for being the ''love of [her] life'' following his support through her pregnancy.

She wrote: ''9.12.17 THE DAY OUR LIFE CHANGED FOREVER ... such an amazing feeling starting our own family , the love I have for our little princess Peggy is one that is so unconditional ! I'd never of been able to do it without the love of my life ... @krissydonners you was my strength ! Thank you ... #myfamily (sic)''

Joanne also posted pictures of Kris carrying baby Peggy out of the hospital.

David and Victoria's brood were said to be ''excited'' about becoming cousins once again.

A source previously said: ''David's kids are excited about having a new cousin, especially Harper.''

David is already an uncle to his elder sister Lynne's five children.