Lilian is Lady Penelope Creighton-Ward's cook, and lives at Creighton-Ward Manor in Foxley Heath.
She and Parker (her Ladyship's butler/chauffeur) are friendly rivals, of sorts; he invariably calls her Lil, as they spar back and forth in the Manor's kitchen.
Beneath that gruff exterior, it appears Parker harbors a genuine fondness for her. In The Cham-Cham, he fancies "taking cook out for a punt," on his afternoon off (perhaps the way to a man's heart truly is through his stomach!).
Lilian appears in Vault of Death and Thunderbirds Are Go. In the "expanded universe", however, Lil would be a regular in the Perils of Parker comic strip, be mentioned in Century 21 Records story The Stately Homes Robberies (retained for its 2015 adaptation), and briefly appear in the novel The Albanian Affair.
By the time of Deadly Danger!, Lil had left Creighton-Ward Manor, in order to move to Wales and take care of her elderly mother. She was replaced by Annie.

Thunderbirds Are Go[]
Lillian's appearance in the movie Thunderbirds Are Go is not widely known, because she is almost completely hidden from view. It is clear however, that when the makers decided to put the entire International Rescue team in the final sequence at The Swinging Star (except for John, who was on duty), they definitely did not forget Lillian.
Trivia[]
- In The Duchess Assignment, the Lilian puppet appears in two different cameo roles: at the Duchess of Royston's gambling table in the French Casino at the start of the episode, and again at the Art Gallery, admiring the Duchess' Braquasso painting, Portrait of a Gazelle. In The Cham-Cham it played a guest at the Paradise Peaks Hotel. In Alias Mr. Hackenbacker, it was seen at the Café Atalante, Paris. In Thunderbirds Are Go, it played one of the reporters at the Press Conference, and a guest at the Swinging Star.