Really? 1) How does she not know? She is certainly old enough, especially in those days. There are pages of her waxing poetic about her child while she specifically states she does not even know the signs of pregnancy. And K/Cleopatra comes across as nowhere near the powerful, intelligent woman she should have.
Perhaps Essex felt as though making Caesar talk in third person so often was impactful enough. Call me crazy but I think major players on the historical stage such as Caesar and Cleopatra should be felt strongly in an HF. The book reads extremely dry and subsequently none of the characters came alive for me. If anything this reads more like a historical fiction version of Cleopatra: A Life, which is to say it added sex and more description to a bland tale.
This is like a blander, more sexualized version of Memoirs of Cleopatra, but really it barely compares at all because Margaret George did such an excellent job with what is known of Cleopatra.