She was the daughter of Tarquin Hartman and his wife Caitlin. She was made aware of her older half sister (Annalise) by Fiona, Annalise's gold-digging mother. Having found this out she set off to find Annalise.

Joanna grew up in Yallingup (Nr Perth) and she was down to earth. Quite the opposite of Annalise, though they both shared good looks. Annalise was envious of Joanna's stable loving home life. She married Rob Evans, a rich businessman whom she taught aerobics. They moved overseas, though she returned when they split up.

Emma Harrison, was invited to join the Australian ballet school but choose to finish her education. She decided to leave university and concentrate on acting full time. Her credits include guest roles in 'Time Trax', an advert for coke and an appearance in the film 'Streetfighter'.