Marie Bansner, Senta Lueck and Chantal Polzin investigate early mother-child / caretaker-child interaction from the perspective of relational language development theory in their PhD theses. Banser and Lueck analyze video data from German mothers with different SES backgrounds and their babies at home during diaper changing situations. Polzin observes caretaker-child interactions in a Tanzanian orphanage. All three theses are choosing a detailed approach in the analyzing the elements, choreography and influencing factors of early child communication.