This study explores how 3-5 year-old children negotiate participation rights during peer play in a preschool in Sweden. The interest is on how they build relations moment-by-moment. I specifically analyze how they negotiate participation rights with a focus on how they include and exclude each other in the ongoing activity. This is an ethnographic study, and the method is inspired by conversation analysis where the verbal and non-verbal interaction is studied sequentially. The findings are that even very young children are capable of advanced social acts when playing together. Such capacities may include face-threatening acts but also solidarity towards one or more participants. It is important that face-threatening strategies are recognized and addressed as soon as possible because children can need help to find alternative ways to behave when in conflict with one another. Otherwise there is a risk that such strategies, when repeated, cause harm to those children exposed.