{"id":"9df939adf02da49f13df844fac8662a2","slug":"9monthold-developed-rash-on-his-thighs-two-days-after","question":"My 9-month-old developed a rash on his thighs two days after the PCV13 vaccine—is this a normal reaction?","answer":"A rash two days after PCV13 is not a typical vaccine reaction. Most vaccine side effects like mild fever or fussiness appear within the first day or two, and the PCV13 vaccine itself doesn't commonly cause rashes as a documented reaction.\n\nThat said, a rash appearing shortly after vaccination can happen by coincidence—your baby could be developing an unrelated viral infection or skin condition at the same time. The timing alone doesn't tell you whether the rash is connected to the vaccine or something separate.\n\nWhat matters now is what the rash looks like and how your baby seems. If it's spreading, if he has fever, or if he seems unwell, contact your pediatrician today. If the rash is localized, not spreading, and he's acting normally, it's still worth describing to your pediatrician at your next visit or over the phone—they can see it or hear you describe it and determine whether it needs evaluation now or can wait.\n\nThe safest approach is to reach out to your pediatrician today to describe the rash and have them assess whether your baby needs to be seen.","sources":"[]","thread_json":null,"topic":"vaccines","view_count":0,"created_at":"2026-10-18T23:00:59.684Z"}