Anna Guy has given birth to her sixth child.
The sister of Scott Guy and ex-wife of Ewen Macdonald announced the new arrival online.
Born on July 23 Guy said Ari Scott Joseph Jameson has a "sweet little face with the cutest chubby cheeks and loads of black hair".
She also reflected on the moment her children saw their new brother for the first time.
"There is something special about the bond between siblings and no matter what happens in life, brothers and sisters will always be the first friends you make."
Anna's father Bryan said the family is "over the moon" about the birth.
"Everyone's doing well... We're absolutely thrilled to have another grandchild, and the other five children are delighted to have another addition to their family.
"We saw them just after the little fella was born and they're just over the moon."
Macdonald was acquitted of killing his brother-in-law Scott Guy in a high-profile trial in 2012. He was jailed for five years for a string of offences including vandalising Guy's new house, killing 19 calves and burning down a 110-year-old building.
Macdonald was released on parole from Rolleston Prison in 2015.