My wife's grandma lived with us for 3 months because she needed care, any deduction?

It depends on if she provides more than half her support for the year and claims her own exemption. 

Did you provide more than half of her support for the year? Were you part of a "multiple support agreement"?

If so, then you may qualify to claim her as a dependent and any medical expenses you paid for her. 

If not, then there are no expenses you can claim for her living with you.

If you qualify to claim her as a dependent, then any medical expenses you had to pay for her might be deductible. 

Please refer to pub 502 under "whose medical expenses can I claim" for additional information about claiming medical expenses on Schedule A, Itemized Deductions.