Hi A.,
Is there a specific nutritional deficiency your baby has that requires additional vitamins? Because if there isn't, she probably doesn't need a supplement. If you are breastfeeding her, you can/should continue taking good quality prenatals yourself, and you will then be passing on all the nutrition your dear little girl needs through your perfect milk. If you are artificially feeding, baby formulas are all fortified with vitamins, so she is also probably getting all she needs of the standard nutrients promoted by the FDA and the American Pediatric Association.
However, if you have any concerns about her nutrition, and she is spitting up her vitamins, I wouldn't give them again, just because you don't know how much exactly she IS keeping inside of her. You might instead try adding them to some other food--you didn't say how old she is and whether she takes anything but breastmilk or formula. If she does, perhaps you can blend in the vitamins that way.