Hal_Al
Level 15

After you file

No, the IRS doesn't make that decision, unless you both file competing claims (tax returns). So, as long as you agree, you can do it either way.
If you mail in your return, claiming the child and he doesn't file the amended return; then you will both hear from the IRS in 9-12 months. But, in the mean time, your return will not be held up.