Mark Zuckerberg, the Meta CEO and Facebook founder, is set to face a pivotal moment in a lawsuit alleging that social media platforms harm children. The trial, which centers on Instagram's impact on young users' mental health, marks the first time Zuckerberg will be questioned in a U.S. court. The stakes are high, as the verdict could potentially erode Big Tech's long-standing legal defense against claims of user harm. This case is part of a global backlash against social media platforms over children's mental health, with countries like Australia and Spain considering restrictions on access for minors. The lawsuit, brought by a California woman who began using Instagram and YouTube as a child, alleges that the companies profited from hooking kids on their services despite knowing the potential harm to their mental health. Meta and Google have denied the allegations, but internal documents have revealed that the companies were aware of potential harms. The trial serves as a test case for similar claims against Meta, Alphabet's Google, Snap, and TikTok, with families, school districts, and states filing thousands of lawsuits in the U.S. accusing the companies of fueling a youth mental health crisis. The outcome of this trial could set a precedent for how social media companies are held accountable for their impact on young users, and it's a question that has sparked debate and discussion worldwide.