The 27-year-old Australian actress, who quit her role as Rachel in the Seven Network family drama last year, is expecting a baby with Packed to the Rafters cast member and real-life fiancé James Stewart in May this year.
Corr told New Idea magazine: "They are in the most love bubbly love bubble. Jess is completely relaxed and so excited about becoming a new mum.
"She will send texts to Jim on set saying, 'I need you back now!' But she's really calm. She is going to be the most amazing mum."
Corr has previously said of Marais and Stewart: "I mean, these are two of the most wonderful people you'll ever meet... and they'll make the most down-to-earth, wonderful parents."
In December, Marais admitted that discovering she was pregnant was a shock, because she was trying to launch her Hollywood career.
She said: "When we found out, that was an issue. But I found that just about every other actress who has had a child and works tells you it can be done and that there is never the perfect time. So we are embracing what we have and looking towards the future with bright eyes."
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