Possibly, depending on his income. The standard deduction for dependents is either $1,050 or earned income plus $350 (up to the maximum normal standard deduction of $12,000)
Ex 1: Dependent has $500 in earned income - standard deduction would be $1,050
Ex 2: Dependent has $5,000 in earned income - standard deduction would be $5,350.
Ex 3: Dependent has $15,000 in earned income - standard deduction would be $12,000.