And Olivia previously revealed she is relishing every second of watching her little boy grow up.
She said: "He is becoming a little individual and his personality is starting to emerge and it's amazing.
"I'm more and more excited to be a mother and to be his mother because I think he's a wonderful little person."
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The Rush actress works tirelessly on various charity pursuits as well as a busy acting career and she is keen for Otis to follow in her philanthropic footsteps when he gets older.
She said: "I look forward to bringing him to [charity events] once he's conscious of what it means because I think it'll be very important for him to have experience with this stuff like I did."
- Bang! Showbiz