You can claim her for the whole year if you provide more than half of her support and she makes less than $4150 in income. ( Per IRS, you are treated as a resident for the whole year for claiming dependent purposes if you are a US resident at any time of the year)
Click here Credit for Other Dependents for rules under Qualifying Relative
Did she enter US as a greencard holder or only a visa? When exactly did she enter the US ( date) ?
You can claim her for the whole year if you provide more than half of her support and she makes less than $4150 in income. ( Per IRS, you are treated as a resident for the whole year for claiming dependent purposes if you are a US resident at any time of the year)
Click here Credit for Other Dependents for rules under Qualifying Relative