Lemierre’s syndrome is an infrequent disease characterized by septic thrombosis of the internal jugular vein followed by pulmonary embolism generally occurring after upper respiratory and gastrointestinal tract infections. We present the case of a 15-year-old female patient with postseptal cellulitis and cervical abscess who developed pulmonary embolism and pleural effusion secondary to internal jugular vein thrombosis. Cultures were positive for <i>Streptococcus anginosus</i>, antibiotic treatment was established with satisfactory clinical outcome. High clinical suspicion is required for a diagnosis. The mainstay of treatment is a multidisciplinary approach based on two essential pillars: antibiotic therapy and surgical drainage. This is an important case because of the unusual presentation, the isolation of an infrequent pathogen, and the primary infection site (postseptal cellulitis), which are rare characteristics of this condition in the pediatric population.