Notice this at the top of the form Caution: The federal income tax on your child’s income, including qualified dividends and capital gain distributions, may be less if you file a separate tax return for the child instead of making this election. This is because you cannot take certain tax benefits that your child could take on his or her own return. For details, see Tax benefits you cannot take in the instructions. 

Maybe filing a separate return for the child would be a more economic approach in your case.