Westside matriarch Antonia Prebble is due to give birth any day, completely at odds with her character Rita West who in the new season set in 1987 is playing a grandmother to three Westie grandkids.

Prebble spent the entire shoot covering up her own burgeoning baby bump. Producers of the hit series say they were delighted when Prebble announced her pregnancy before filming started in February, but admit the news brought complications.

Rita West has an adult son, Wolf (played by Australian actor Reef Ireland) and is grandmother to twins Van and Jethro and baby Pascalle, so there was definitely no way to write her own pregnancy into the show.

The busy actress was still filming the show at 36 weeks, which meant the costume department had to produce innovative ways to mask the pregnancy.

Antonia Prebble and fiance Dan Musgrove. Photo / Herald on Sunday.
Antonia Prebble and fiance Dan Musgrove. Photo / Herald on Sunday.

Head Costume designer Tania Klouwens said Prebble had only a tiny baby bump when they started filming.

"But from the get-go we gave her a great 1987 leather jacket, that was a perfect disguise whenever she left the West house, and introduced "house coats" for her indoor scenes, which were basically tasselled kimonos that would help hide the bump as it got bigger. Very Stevie Nicks. That way we weren't suddenly introducing them when she got bigger.

"We also had a bunch of crossover tops made, that were quite forgiving as they billowed a little bit around the tum, while still looking suitably 'Westie'. Mostly we were just super-lucky that Antonia only put on weight on her bump. With the right angles, and a bit of patterned fabric, it was hard to tell she was actually really, really pregnant by the end."

The camera department and art department also had to get a little creative toward the end of filming, with props and camera angles becoming a pivotal part of the cover up.

"It was a lot about body position. We found that if I faced the camera directly, that really helped disguise the bump," says Prebble. "Towards the end of the series things got a bit more tricky and the art of disguise was used."

Prebble and fiance Dan Musgrove, who plays Lefty Munroe on Westside, are now gearing up for the arrival of their baby, which could be any day now. The actress, who has given birth five times on screen for various shows, is excited about the future.

"Now that we have finished the series, Dan and I are into baby-prep mode. We are really excited about moving into this next stage of our lives and welcoming our little one into the world."