'You look like sisters!' another added.
Seeing double! After she posted the photo, fans couldn't get over how much they look alike
In her post, the journalist and lawyer said she shared a 'powerful connection' with her firstborn, but clarified that it wasn't favouritism in any way.
'First born. There's something powerful about the connection with a first child. It's not favoritism or anything of that nature,' Antonia said.
She added: 'Rather, I think it's because there is a period of time where there are no other beings vying for your love and attention and your focus and devotion is entirely to them.'