Research on child-agent interaction is rapidly expanding. It is, therefore, necessary to converge our collective efforts to broaden our understanding and perspectives of how virtual agents, affect and potentially improve the well-being of children. "Children, Robots and Virtual Agents: Present and Future Challenges" follows our International Conference on Social Robotics (ICSR) 2020 workshop on child-robot interactions. In this full-day workshop, we will focus on the unique technical and empirical challenges of designing and conducting child-agent interactions. In light of the current pandemic situation, we will also address the challenges and adaptations of conducting research under the "new normal" to understand how researchers overcome these challenges and what we can learn and keep in the future. We also aim to join the virtual agents and robotics communities to learn from each other and discuss both areas' common and specific challenges. Our primary goal is to provide an opportunity for an interdisciplinary debate about the present and future of child-agent interactions. We want to bring together researchers, practitioners and pioneers from relevant disciplines and create collaboration opportunities. As part of the workshop, we will have a collaborative activity where our participants will work together and brainstorm about intelligent agents in different time frames (past, present and future). We will also have a panel of experts discussing the topics of this workshop and answering participants questions.