Penny, sorry I made and error in my posting the mother of Dorothy Jean Ada EVANS should have read Dorothy EVANS not Jean EVANS.So sorry, no wonder you are confused.
I did find this entry on the 1922 electoral roll, and wondered if it was your Gwilym EVANS. The location is in Rockhampton, Queensland. QFHSdatasearch Version 1.9.12 by Queensland Family History Society Inc. From [Commonwealth Electoral Roll (Queensland) 1922] database No: 1724 Surname: EVANS Given Names: Gwilwm Thomas Title: Place of Living: 58 Talford st. Occupation: accountant Sex: Male Subdivision: Fitzroy Division: Capricornia ID: 57064