At the memorial gallery of the late Chinese artist Zhang Leping, an entire wall at the exit is covered with messages left by admirers touched by the story of Sanmao, the comic character Zhang created.

One message from a mother to her son reads: "Dear Ai Ai, you are now five years old. This is the first time your father and I have brought you to this gallery. We trust that in the future you will discover more beautiful things and that the world will treat you gently."

A teacher writes: "The story of Sanmao is such a poignant one that it will be remembered for a long time to come."

When the memorial gallery was inaugurated last year visitors formed long queues as they waited to enter. Zhang Weijun, the youngest child of the late artist, says the venue still draws large crowds.

Sanmao's enduring popularity extends to publishing as well. Wang Yunmei, an editor with Juvenile and Children's Publishing House in Shanghai, says the Sanmao series titled The Winter of Three Hairs, first published more than 70 years ago, is still a bestseller.

"With our Shanghai Century Publishing Group the series is always one of the best sellers. Sales of the series started to rebound in about 2010 and it has since been among the top five books for the group every year."

While the children of today live in a world very different to the one that Sanmao inhabited, his story is one that still evokes amusement and admiration, she says.