With its naked tennis matches, mile-high club dalliances and outdoor romping, bonkbuster Rivals is the TV hit of the autumn.
And given its racy storylines, producers of the Disney+ show must have been left in a panic when Dame Jilly Cooper asked them to find roles for her young granddaughters in the adaptation of her 1988 novel.
They did, however, manage to find the perfect parts for the teenagers – casting them as David Tennant’s on-screen daughters.
Scarlett and Sienna, the daughters of Dame Jilly’s son Felix, appear in the first episode.
A Rivals insider told The Mail on Sunday: ‘As executive producer, Dame Jilly was on set a lot, but you could tell her favourite day was when her granddaughters appeared as David’s children.
Dame Jilly Cooper found parts for her teenage granddaughters in the Disney+ adaptation of her 1988 novel Rivals
Scarlett and Sienna, the daughters of Dame Jilly’s son Felix, appear in the first episode appear as David Tennant’s on-screen daughters in the first episode
‘It was such a wonderful occasion, a real family affair and so lovely for Dame Jilly to have the girls there.’
The pair are seen running to meet Tennant, 53, who plays television tycoon Lord [Tony] Baddingham, as he lands a helicopter on the lawn of his Rutshire estate.
The Doctor Who star embraces Scarlett and Sienna and they turn to face the camera as he kisses them on the head before they run out of shot again as he nonchalantly thwacks a croquet ball.
Dame Jilly’s 18-year-old grandson Jago was part of the crew for the show and, according to sources, ‘worked harder than anyone else on set to make his grandmother’s vision come alive’.
His hard-working reputation meant that when she visited the set, Dame Jilly, 87, was better known as ‘Jago’s granny’.
Rivals, which also stars Poldark’s Aidan Turner and Emily Atack, has gripped the nation and won praise as a glorious no-holding-back adaptation of the Eighties bonkbuster and for its accurate recreation of that era.
Dame Jilly made her own surprise cameo in the fifth episode when viewers see writer Lizzie Vereker, played by Katherine Parkinson, pay a visit to her book agent in London.
After a long lunch, the agent, played by Felicity Kendal, reads her bonkbuster aloud – much to the amusement of a woman at the neighbouring table.
Viewers were delighted to see that the chuckling woman was none other than Dame Jilly.
Dame Jilly with the cast of Rivals, including David Tennant, Aidan Turner, Deborah Armstrong and Liam Keelan
The writer’s daughter Emily and her husband Adam have three sons – Jago, Lysander and Acer – while son Felix and his wife Edwina have Scarlett and Sienna.
Dame Jilly has admitted the relationship with her five grandchildren has strengthened since they grew up, saying: ‘I can communicate better with them now that they aren’t babies.’
Speaking to the Mail in 2012, Dame Jilly said: ‘I don’t think I have ever babysat, that’s the awful thing. I do love them but I just don’t want to smother them with cuddles.
‘I’m not one of those grandmothers who is obsessed with their grandchildren. But I think as they get older, I will come more and more into my own.’
By securing two of them a role in the most talked about show of the year, Dame Jilly appears to be fulfilling that prophecy.
