The two characters first appeared in Topsy And Tim’s Monday Book, originally published by Blackie in 1960.
It was unusual for ordinary children to be the lead characters in picture books, but the Adamson said they put youngsters at the centre of the narrative “because all the world is magic for children”, and the choice of girl and boy twins was a way of ensuring gender equality.
The series has been in print for more than 60 years and has sold over 25 million copies around the world.
In 1984, the book series was adapted into a 60-episode animated TV show, and since 2013 three seasons of a live-action version have broadcast on CBeebies, winning the Bafta Pre-school Live Action award in 2016. The series still regularly airs on CBeebies.
Adamson’s former agent, Mandy Little, said the twins were “close to her heart for, as she once told me, they were based on herself and her beloved brother Derek, who were inseparable as children”.
Adamson was made an MBE for her services to children’s literature in 1999, and in 2016 was made an honorary fellow of Goldsmiths College.
