( April 21, 2026, 4:26 PM EDT) -- BOSTON — Contending that a children’s advocacy group and others who sought to intervene in a lawsuit to block recent changes to the Centers for Disease Control and Prevention’s vaccine recommendations and its advisory committee could not show that their motion to intervene was improperly denied, the federal government moved the First Circuit U.S. Court of Appeals for summary disposition of the would-be intervenors’ appeal of the denial of their motion by a Massachusetts federal court....