You might as well sit down right now and figure out who gets to claim your daughter as a dependent.
If you daughter took the personal exemption - which she probably shouldn't have done - the she needs to amend her income tax return. If your wife claimed her as a deduction then you need to figure out who actually gets to claim her.
Here's the IRS's rules:
1.The child must be your son, daughter, stepchild, foster child, brother, sister, half brother, half sister, stepbrother, stepsister, or a descendant of any of them.
2.The child must be (a) under age 19 at the end of the year and younger than you (or your spouse if filing jointly), (b) under age 24 at the end of the year, a student, and younger than you (or your spouse if filing jointly), or (c) any age if permanently and totally disabled.
3.The child must have lived with you for more than half of the year.*
4.The child must not have provided more than half of his or her own support for the year.
5.The child must not be filing a joint return for the year (unless that joint return is filed only to claim a refund of withheld income tax or estimated tax paid).
* time at college is usually deemed to be a "temporary abscence" and is included as time the child lived with you.
If the child meets the rules to be a qualifying child of more than one person, only one person can actually treat the child as a qualifying child. See "Qualifying Child of More Than One Person" here
https://www.irs.gov/pub/irs-pdf/p501.pdf#en_US_2016_publink1000220917
to find out which person is the person entitled to claim the child as a qualifying child.
Tom Young
