This data-based theoretical paper explores the contrasting tensions of adults being in "solidarity" with youths while not reproducing systems of oppression through adultism. Written by adults who have been engaged side-by-side with youth activism, the purpose of this article is to better understand what adult solidarity and support look like according to youth activists themselves as we grapple with the unintentional mechanisms of reinforcing oppressive power dynamics between young people and adults in activist communities. Extending on the Gaztambide-Fernández's (2012) notion of "relational solidarity," the findings offer four types of actions (modeling, connecting, supporting, and protecting) adults can do to authentically support youths and thereby adds conceptual clarification and nuance for adults seeking to work in solidarity in more authentic youth adult partnerships (YAPs).