Two of Arns' memories were of seeing her father go door-to-door on his horse to help contain a smallpox epidemic and watching her mother arrange for a sick neighbour to be taken to the nearest hospital on the back of a cart, a journey of three hours.

Arns further studied public health, with the aim of assisting poor children in environments plagued with high child mortality rates, malnutrition and violence.

After she worked in local hospitals tending to infants, she was then given charge of a string of clinics on the impoverished outskirts of the southern city of Curitiba.

Her approach was based on familial education in order to help decrease the rates of petty crime and preventable diseases.

[8] Arns was killed by the Haiti earthquake of 12 January 2010 in Port-au-Prince,[9] where she was carrying out humanitarian activities on behalf of Pastoral da Criança.