Dehydration: This is the most common reason for strong-smelling urine in children. When the body is not taking in enough fluids, the urine becomes more concentrated, leading to a stronger odor.

Urinary Tract Infection (UTI): Bacterial infections in the urinary tract can cause a strong, unpleasant odor in the urine. UTIs are more common in girls, but can occur in boys as well.
Diet: Consuming certain foods like asparagus, garlic, or onions can make urine smell stronger due to the breakdown of sulfur compounds.
Constipation: Fecal impaction or constipation can cause urinary retention and concentrated urine, leading to a stronger odor.

Diabetes Mellitus: Uncontrolled diabetes can lead to ketones in the urine, causing a sweet, fruity odor. Missing this diagnosis can lead to serious complications, including diabetic ketoacidosis.
Kidney Disease: Certain kidney diseases, such as kidney failure or polycystic kidney disease, can cause changes in urine odor. Early detection is crucial to prevent progression of the disease.

Maple Syrup Urine Disease: A rare genetic disorder that causes the body to be unable to break down certain amino acids, leading to a sweet, maple syrup-like odor in the urine.
Phenylketonuria (PKU): A genetic disorder that causes the body to be unable to break down the amino acid phenylalanine, leading to a musty odor in the urine.
Urethral Stricture or Obstruction: A blockage or narrowing of the urethra can cause urinary retention and concentrated urine, leading to a stronger odor. This is a rare condition in children.