This infant likely has infantile colic, defined by the “rule of 3s”: crying >3 hours per day, >3 days per week, for >3 weeks, usually starting in the first few months of life. It is benign and self-limited, typically resolving by 3–4 months of age.

Toronto Notes 2023 – Pediatrics, “Common Concerns in Infancy”:

“Colic is self-limited. No routine testing is required in healthy, thriving infants. Reassurance and support for parents are key.”

MCCQE1 Objectives (Pediatrics > 78-1: Behavioral Pediatrics):

“Candidates must recognize normal variations such as colic and avoid unnecessary interventions. Counseling and reassurance are essential.”

Sedatives (D) are contraindicated. Investigations (C) are unnecessary without red flags. Resolution (B) usually occurs by 3–4 months, not as late as 12 months.