Three-year-old filly Kay Cee has given the Parnham family an historic win in the Group One Kingston Town Classic at Ascot.

Trained by Neville Parnham, Kay Cee ($11) was ridden by his son Steve in Saturday's 1800m-race, the final Group One race of the year in Australia.

Kay Cee is a daughter of Playing God who Neville Parnham trained to win the Kingston Town in 2010 and 2011, with Steve aboard both times.

The jockey got down to ride Kay Cee at the featherweight of 50kg and was rewarded when she strode past veteran Gailo Chop ($41) to win by half a length with Godolphin's Best Of Days ($5.50) the same margin third.

"It's the best feeling I've ever had on a racetrack," Steve Parnham told Sky Thoroughbred Racing.

"I've worked so hard. The biggest challenge was to get my weight down.

"Playing God was my first Group One and to win on one of his progeny is unbelievable. I'm just so happy."

Kay Cee jumped from gate one and got a trail behind Gailo Chop and burst clear in the straight.

Neville Parnham said it was particularly satisfying to win with a daughter of Playing God.

"It's a very big thrill to win with a horse I think a lot of," he said.

"And she's by Playing God. His sire Blackfriars is no longer with us so it's great for Western Australia to have another good sire."

Parnahm said he had faith in his son's race tactics.

"Steve is a great form student and I knew he had a plan," he said.

"He just wanted to have the favourite in his sights. I was very positive about barrier one although others were not so sure.

"But as I said, Steve is great at his form and he rode to his plan."

Favourite Tuscan Queen ($4.60) made her move around the turn but could only manage seventh.