Intuitively, even very young children can act jointly. For instance, a child and her parent can build a simple tower together. According to developmental psychologists, young children develop theory of mind by, among other things, participating in joint actions like this. Yet many leading philosophical accounts of joint action presuppose that participants have a robust theory of mind. In this article, I examine two philosophical accounts of joint action designed to circumvent this presupposition, and then I proffer my own novel (...) account of what makes (at least some) interactions between very young children and others joint. I argue that children can take up without deliberation intentions with a joint content that have been transmitted to them by others. In doing so, children can come to share intentions with others, and by acting on these shared intentions they can come to act jointly, all without employing a robust theory of mind. (shrink)