In light of the growing phenomenon of parent-child digital co-play of online games, we conducted a study to understand the different ways of digital co-play and how they can offer opportunities for the child's learning. We analyse four cases of parent-child digital co-play on "Let's Play" gaming videos with "Roblox" on YouTube. Our research method adopts a netnography research approach and multimodal discourse analysis to examine the data. We identify three ways of digital co-play, which include the parent-directed, parent-child negotiated, and child-directed parent-child interaction styles from the analysis of the videos. Following the analysis, we discuss how each of the ways of parent-child digital co-play can be productive in helping the child learn through shared gameplay with parents. We suggest how children can learn through communicating with parents during gameplay, creating something by themselves in the game, modelling parents' in-game behaviour, teaching their parents by sharing their knowledge, and leading the co-play. Our study aims to serve as a conversational starter to contribute to the global discourse on the phenomenon of parent and child shared interactions with digital technology as well as the ways in which learning can be facilitated through such experiences.