The Wedding Gift is a silver vase which is worth 2 less than an ordinary silver vase. This vase is found in the basement of Gweden Farm during the quest "The Siren's Deception." As the female gang are targeting married men, it is possible that this was one of their thefts.
It can only be obtained during the quest, as the farmhouse becomes locked afterwards (requires key) and the key is unobtainable. It is unable to be returned to any previous owner.