You actually can choose who claims your daughter if you all were living together after her birth.  (Your then boyfriend and now husband was considered temporarily absent while away at boot camp, which means he also lived with your baby all year for this purpose).  Congratulations by the way, on her birth and your marriage.  For 2018, you will not file a joint return because you did not marry until 2019 (albeit right on January 1).  But while you will file separate returns, you can compare who gets the greater benefit by claiming her.    However, while either is allowed to claim her, both of you cannot do so (to try to split benefits, for example).