You should leave one
exemption for yourself and have your spouse claim 3.
From the IRS instructions for Form 8379, “Allocate the exemptions
claimed on the joint return to the spouse who would have claimed them if
separate returns had been filed.”
Any credits related to your children would be allocated to the
injured spouse as well.
Also, be sure that when you are filling out the form that you
indicate that your spouse is the “injured” party.
