Joyce lost his cabinet position and the Nationals leadership in February, after it was revealed he and Campion - his former media adviser - were expecting a child. In April, Campion gave birth to their son, Sebastian.

On social media, many vowed not to watch Sunday Night, expressing their disgust at the couple for accepting an interview payment. Claims the fee would be set aside for Sebastian did little to diminish the outrage.

But clearly, plenty of people did tune in.

According to Joyce and Campion, they did it for their son, arguing that if everyone else was making money from this story, he should at least get a cut. Somewhat less plausibly, they also suggested media scrutiny would abate after the interview.

Instead, it (predictably) intensified, with focus shifting to the questions they weren't asked. Including: What were the circumstances behind Campion's move to other parliamentary roles following her departure from Joyce's office? And who paid for their trip across Australia's east coast last year?

Ultimately, the biggest winner was not the couple or their son - or even Sunday Night.

Instead, it was Seven's reality show House Rules, which aired directly before the interview.

The show attracted its biggest audience this year: a national average of more than 1.4 million, beating MasterChef and The Voice for the first time.

If this ratings "baby bump" proves to be more than a one-off for House Rules, Seven - in a roundabout way - will have gotten its money's worth.

So far this year, Sunday Night has drawn smaller audiences than arch-rival 60 Minutes. Last night, a late edition of Nine's current affairs show averaged just 626,000 national viewers.

Overall, Seven's 6pm news was the top-rating program (1.76 million) while ABC enjoyed an unusually strong night thanks to David Attenborough's Tasmania (1.2 million) and the premiere of Australian drama Mystery Road (1.2 million).