Septic shock is a severe condition caused by infection leading to dangerously low blood pressure. This study compares two fluids used in treatment: "normal" saline (NS) and balanced fluids (BF) like Lactated Ringer's and PlasmaLyte. It aims to see if BF is more effective and safer for children with septic shock, especially in preventing kidney injury (damage to the kidneys). About 5,000 children die from septic shock yearly in the US. All children in the study will receive initial care in the emergency department. The study will take place across 30+ locations and will include children aged 2 months to under 18 years. The study will assess major kidney issues and other health markers within 30 days.

• Participation involves giving at least one fluid bolus and possibly more if needed.
• The study requires parental consent but may proceed under specific emergency conditions.
• Participants should not have certain health concerns, like severe liver or kidney problems.