Teresa Young was married to a Portuguese man. She was probably the sister of Hazel Hardy, in which case she too would have been originally Irish.
In the summer of 1943 the wife of British Army Aid Group agent 68 escaped from Hong Kong and made her way to Waichow, where she was debriefed as to her experiences in prison, where she'd been questioned about her husband's activities. She said that certain former Stanley internees she'd seen in Stanley Prison had been identified by fellow-prisoner Teresa Young, who'd seen them in camp.
She also stated that she believed one of the prisoners she herself saw from Shamshuipo POW Camp was (R. J.) Hardy, who had been engaged before the war to Young's sister. Immediately the war ended, Hardy married his fiancee, Hazel, which makes these identifications likely but not certain.
It's also not clear why a person of either Portuguese or Irish nationality should have been in Stanley, although Japanese racial policy was rather chaotic so it's certainly not impossible.
She was presumably allowed to leave Stanley and later arrested, perhaps for the kind of illegal relief activity carried out by her sister.
Source: Waichow Intelligence Summary, July 30, 1943 (part of the Ride Papers, held at the Hong Kong Heritage Project).