In recent years, political parties and politicians have begun to use public Facebook "pages" not only for the purpose of self-presentation but also to aim at entering into direct dialogues with citizens and enabling political discussions. Not only the owner of the page but also any people who are politically interested can create politically relevant postings on the "Wall" of the page. These "Wall posts" often exhibit sentiment associated with certain political topics, political parties or politicians. In this paper, we seek to examine whether sentiment occurring in Wall posts on public political Facebook pages has an effect on feedback in terms of the quantity of triggered comments. Based on a data set of 5,626 Wall posts from Facebook pages of German political parties and politicians, we find different significant relationships between the quantity of words indicating positive and negative emotions in a Wall post and the number of its corresponding comments. Furthermore, our results show that positive as well as negative emotions might diffuse in the subsequent comments.