if it is a female that came back set her up a large dog bowl with pine needles or pine shavings ect in it, and see if she lays in a week or so, as she could have been fertilized, and may lay and raise another pair for you. id take her inside for now having that something or one got at and released ect them, till you find out what and how and stop it from happening again. put it on layer pellets just in case fertilized female (extra protein ect and calcium ive found helps chances of hen eggs and squabs through incubation and rearing time, and eggs are fertilized inside week to months before they are layed at times). this is just all if they were especially expensive or valuable or you couldnt get more. good luck and post some pics. i miss my capuchine i had to give away when moved. males may have slightly bigger crest than female, if it was remembered and was noticeable.