3rd Party Sick Pay reporting

Hello,

 

My son received money for Third Party Sick Pay.  There is no Fed tax withheld, but there is an amount listed in Box 1 as well as SS Tax and Medicare tax withheld.

 

This amount puts him over the $4,400 where I could no longer claim him as a dependent.  

Does the IRS consider this sick pay as wages?

 

Thank you.