Which finding at 6 months would be considered abnormal during a growth and development assessment?

• A. Weight gain of 4–7 ounces per week
• B. Length increase of 1 inch in 2 months
• C. Head lag present
• D. Can sit alone for a few seconds

Answer: (C)

At six months, a key area being assessed is neuromotor development, specifically head control. By this age, infants should have good neck and trunk strength and no longer demonstrate head lag when pulled to sit. Head lag means the head flops backward instead of remaining in alignment with the body, which indicates delayed neuromotor development or hypotonia. That’s why finding head lag at six months is abnormal and would prompt further assessment.

The other options fit typical growth patterns at this age: weight gain of about four to seven ounces per week is expected, length should increase steadily (about a centimeter per month), so gaining about an inch over two months is plausible, and many six-month-olds can sit with support and may sit briefly without support.