My deduction for supporting my adult disabled child is not showing. what do i do?

My adult son, age 22, receives Social Security Disability.  he lived with me for 7 months last year and earned less than $2,000.  I have entered this information, but it is not showing.  What do I do now?
As bwa indicated, there is no specific deduction for an adult disabled child. But he may be a "Qualifying Child" for the Earned Income Credit and the $3700 "exemption" (deduction) for being your dependent.

BUT, if he is receiving Social Security Disability Income(SSDI), he may not qualify as you dependent or qualifying child. Living  with you for 7 months and earning less than $2,000 is not enough for him to qualify.
A child of a taxpayer can still be a “Qualifying Child (QC)” dependent, regardless of his income, if:
1. he is under age 19, or under 24 if a full time student for at least 5 months of the year, or is totally & permanently disabled
2. He did not provide more than 1/2 his own support
3. lived with the parent (or was temporarily away, such as school) for more than half the year

So, it doesn't matter how much he earned. What matters is how much he spent on support. SSDI is his money and the SSDI that he spends on his own support counts against you being able to claim him. Money he put into savings does not count as support he spent on him self.
The support value of the home you provided is the fair market rental value of the home plus utilities & other expenses divided by the number of occupants.

A person can still be a dependent, if not a Qualifying Child, if he meets the 6 tests for claiming a dependent:
1. Closely Related OR live with you ALL year
2. His/her gross taxable income for the year must be less than $3,700 (2011)
3. You must have provided more than 1/2 his support

In either case:
4. He must be a US citizen or resident of the US, Canada or Mexico
5. He must not file a joint return with his spouse or file a tax return claiming someone else as a dependent
6. He must not be the qualifying child of another taxpayer

bwa asked " Is he showing up as a dependent on your tax return?"

Look at your actual tax return. The  main Form 1040, 1040A or 1040EZ can be seen through Tools, View Tax Summary, Preview My 1040. Is he shown on line 6c?
    I'm not sure what deduction you are referring to, but it sounds like you should be entitled to claim him as a dependent.  Is he showing up as a dependent on your tax return?
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