Joanna also made an announcement on her Instagram account, sharing a sweet photo of Blainey with the caption:
"Blainey Ann Burgess. Our precious girl entered the world on 28.7.19 (on her due date 👏🏻)💗💗So blessed, so in love and in a total newborn love bubble 💗"
In a second post, the mother-of-three posted a photo of the entire family, captioning it, "Our family coming together to meet our newest member BLAINEY - a total pinch myself moment. heart is full 💜"
The news follows George's announcement of his departure from the South Sydney Rabbitohs, where he played alongside his brothers Sam and Tom Burgess.
George is set to move to his native UK on a three-year contract with Wigan Warriors in 2020.