The Sheffield born Olympian announced this morning via Twitter that her second child is on the way.
She posted a picture on her Instagram account of her two-year-old son Reggie holding a book that says: “I’m going to be a big brother.”
Jessica won silver in the Rio Olympics for her performance in the heptathlon before announcing her retirement last year in October.
She and her husband Andy Hill became parents in July 2014 after she shot to fame in the 2012 Olympics, and say they are: “So happy!”
The Olympian was made a dame in this years New Year’s Honours List.