KnowMed notes and RACGP guidelines offer clinical guidance on periorbital and orbital cellulitis in children, emphasizing the critical difference between the two conditions, which are infections either anterior or posterior to the orbital septum, respectively. The Royal Children’s Hospital Melbourne provides detailed clinical practice guidelines outlining the assessment, management, and specific antibiotic treatment protocols for mild, moderate, and severe cases, noting that orbital cellulitis is a surgical emergency. The second source, a medical case study and Q&A, supports this by presenting a patient case that transitions from periorbital to orbital cellulitis, detailing the diagnostic signs like painful eye movements and proptosis that suggest the severe, vision-threatening orbital infection. Both texts stress the need for urgent specialist consultation (ENT and ophthalmology) and imaging when orbital cellulitis is suspected.