Can I write off mileage and parking from taking my sister-in-law top chemo?

[xmasbaby0]

Is she a dependent on your own tax return?  You can claim such expenses for yourself, your spouse or dependents on your return.

[Hal_Al]

There is one exception to the requirement that the person with medical expenses be  yourself, your spouse or your dependent. 

If your close relative cannot be your dependent because he had more than $4,200 of gross income, but otherwise would have qualified as your dependent (basically that you & other family members provided more than half his support), then you can include in your deductible medical expenses any qualifying medical expenses you paid on his/her behalf just as if he/she was your dependent.