Aidan O'Brien's daughter of Galileo claimed a Curragh maiden in June and really caught the eye to win this seven-furlong Group Three.
Easter Lily made most the running, closely tracked by Dawn Delivers and then Happily, the Ryan Moore-ridden 8-11 favourite.
The latter was nudged wide as the field straightened for home and coolly gained a definitive lead she would not relinquish.
Happily showed marked improvement the further she went and was much too classy for Shalailah, who was also second behind the O'Brien inmate at the Curragh.
O'Brien said of the five-length winner: "You'd be delighted with that. She looks like she's come forward again.
"You could look at the Debutante (Curragh, August 20) and then the Moyglare (Curragh, September 10).
"We'll take it one race at a time but you'd imagine something like that.
"She's lovely and Ryan is very happy with her. She picked them up very easily.
"Donnacha (O'Brien) loved her the first day and the second time, and I'd say she has jumped again."