Fancy Blue, who gave Donnacha Brien his first Classic success in the Prix de Diane at Chantilly last month, is among 12 confirmations for the Juddmonte Irish Oaks at the Curragh on Saturday.
As expected, his father Aidan has taken out his impressive 1000 Guineas and Oaks heroine, Love.
O'Brien senior is responsible for half of the possibles as he seeks to win the race for a sixth time.
Leading his team is Irish 1000 Guineas scorer Peaceful, who was a close third to Fancy Blue in the French Oaks, and Ennistymon, runner-up to Love at Epsom.
Jessica Harrington is represented by Cayenne Pepper. She made a pleasing seasonal debut when finding only Magical too good in the Pretty Polly Stakes.
O'Brien senior has six of the 15 acceptors as he goes for a 14th success in the GAIN Railway Stakes. They include Admiral Nelson, who disappointed when favourite for the Coventry Stakes at Royal Ascot.
Romanised, winner of the Paddy Power Minstrel Stakes 12 months ago, could make his seasonal debut in the Group Two over seven furlongs.
Ken Condon's five-year-old could face strong opposition with the 16 confirmations including Lancaster House, Speak In Colours and Vatican City.
Last year's shock Irish Derby winner Sovereign features among 14 possibles for the Comer Group International Curragh Cup.
His trainer Aidan O'Brien has six others in the race while his son Joseph has three, headed by last year's winner Twilight Payment.
The latter trainer has given Speak In Colours an alternative entry to the Minstrel Stakes in the Sapphire Stakes on Sunday's card at the Curragh, for which there are 10 possibles.
The five-year-old grey is on a hat-trick after Group victories in the Greenlands and Ballycorus Stakes on his last two starts.
Denis Hogan's Make A Challenge could turn out again after landing a Listed success on this course last week.