"What Are You Concerned About? Classifying Children's and Parents' Concerns Regarding Online Communication", lecture by U. Hasebrink, M. Rechlitz, S. Dreyer and C. Lampert at the 7th European Communication Conference (ECC) of the European Communication Research and Education Association (ECREA) on 1 November 2018 in Lugano (together with N. Brüggen and C. Gebel).