Table 1 Examples of difficult situations related to healthy diet, PA and SB discussed in the questionnaire

Difficult situations PA

1. Before Thor leaves for the youth movement/sports club, he suddenly says that he does not want to go. For years, he has always enjoyed himself and has been enthusiastic about the activities, but today he protests upon departure.

2. Frank is about to cycle to school together with his daughter Marie. Marie complains that she is tired and wants to go to school by car.

Difficult situations SB

1. On a Saturday afternoon at 2 p.m., Martine and Peter are doing the housekeeping (cleaning the table, washing the dishes, ironing, hanging out the laundry, …). Their child Stef asks to watch TV.

2. Luca has been playing for half an hour on his Nintendo. His mother thinks he has played long enough and tells her son to quit, but Luca does not want to stop playing.

Difficult situations healthy diet

1. Wout’s family is having dinner together. Wout finished his potatoes and meat but leaves his vegetables untouched. He refuses to eat the vegetables because he does not like them.

2. At breakfast, Liza refuses to eat her sandwich because she does not feel hungry.