'Of course I said yes’, read the caption next to a series of stunning snaps.
'I was silent for a bit, shocked and stunned, but I am incredibly happy.'
The couple were originally introduced to each other via friends.
Ben recently told the Courier Mail that marriage and kids were definitely on the agenda.
'Definitely, when the time is right,' said Ben.
Added Erin: 'He's the kid-mad one and I'm sort of a few years away from that now but he'd have one tomorrow if he could.
'He's good friends with my manager (Morgan Barta) so I'm sure those two will sort it out and schedule it!'.
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