5 year old receives $14,376 of social security and 1099R from the Navy for $8332 because dad passed away. The 1099R dist code is 7. The SS is not taxable, but the tax on the $8332 from the navy is $1220. 

Mom claims the son on her return, and has zero taxable income because her SS is not taxable (very little other income) and she has lots of itemized deductions for the house. 

I need to file the son's return separately, correct? We can't add his income onto her return where there are extra deductions to be able to absorb some of this income? Seems like the tax is high for the kid. Am I missing anything?