When Blanchett was asked if she was pregnant, she responded, "Yes, I am." But she shook her head when asked if it is going to be a third boy.
"You know more than me," she said. "It's early days yet. It's due in April."
Blanchett is married to director Andrew Upton and works with him as artistic director for the Sydney Theater Company.
Rush said he and Blanchett are working on a stage project there next year.
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