Signe Hammarsten-Jansson Hammarsten-Jansson designed over 200 stamps. The couple had three children in total: Tove Jansson, Lars Jansson and Per Olov Jansson. Born to artistic parents, the children grew up in a Bohemian lifestyle, and all became artists in their own right. Tove became a writer and painter and would gain particular fame for her "Moomin" series. Lars became a cartoonist, ultimately becoming responsible for the "Moomin" comic strips as well as a later animated version. Per Olov became a photographer and collaborated with Tove on a few books. The children were directly influenced by their mother's artistic sensibilities and Tove in
Finnish name share the same surname. All persons have the right to change their surname once without any specific reason. A surname that is un-Finnish, contrary to the usages of the Swedish or Finnish languages, or in use by any person resident in Finland cannot be accepted as the new name, unless valid family reasons or religious or national customs give a reason for waiving this requirement. However, persons may change their surname to any surname that has ever been used by their ancestors, if they can prove such claim. Surnames behave like regular words when forming grammatical cases. Thus, for example,