@DMarkM1 thanks, but I went through the IRS website Q&A & it says, I can claim son as dependent. They do ask, if son has gross income > $4,300. Since, it was a loss, I can claim it? Age is not a factor on that website?
Here is the link to that Q&A
https://www.irs.gov/help/ita/whom-may-i-claim-as-a-dependent
