Context: Advance care discussions (ACD) between health care professionals (HCPs) and parents of children with a life-limiting disease are a core element of successful pediatric advance care planning (pACP). Yet, they are perceived as a challenging situation for all participants. Objectives: Our goal was to investigate the first step of ACD and identify its challenges and helpful communication strategies to develop a conversation guide for initiating the pACP process and structure the conversational opening. Methods: We performed a participant observation of 11 initial ACD and 24 interviews with 13 HCPs and 20 parents of 11 children cared for by 3 different palliative care teams in southern Germany. Qualitative data collection was supplemented by a questionnaire. Content analysis and conversation analysis were used for evaluation. Results: Parents and HCPs start the process with different expectations, which can lead to misunderstandings and confusion. HCPs gain parental cooperation when they express the purpose of the meeting clearly and early, provide structure and guidance, and give parents time to talk about their experiences and feelings. Addressing dying and death is hard for both sides and requires a sensitive approach. Conclusions: Initiating ACD is extremely challenging for all participants. HCPs and parents should clarify expectations and aims at the beginning of the conversation. Future research should focus on how HCPs can be trained for this task and how the right timing for introducing ACD to families can be identified. Clinical Trial Registration number 049-12.