Epidemic still has a way to go to emulate her elder brother Impending but her trainer James Cummings believes she is on an upward spiral.
By champion Lonhro out of dual Group One winner Mnemosyne, Epidemic won her third race from eight starts when she took out Saturday's 1100m fillies and mares race at Rosehill in a photo-finish from O'Rachael.
While she is unlikely to reach the standard Impending did a year ago when he won the Stradbroke Handicap as a three-year-old, she will probably be given her chance at a black-type race during the Brisbane carnival.
"This is a springboard for her to better races," Cummings said.
"She has already been placed at stakes level and now the aim is to get a black-type win with her.
"She has a terrific attitude and has black-type written all over her."
The margin between Epidemic and O'Rachael was a nose and her jockey Brenton Avdulla admitted he was unsure of the result.
"You often miss in these finishes," he said.
"I've been having a lean month.
"Halfway up the straight I thought I'd get there and then I didn't think I would and in the end I was happy I did."
Avdulla began the day nine wins ahead of Blake Shinn in the Sydney premiership which he lost narrowly last season when caught by Hugh Bowman in the final few weeks.