How are you trying to tame them?
I don't handle or try to tame my linnies every day. What I do is offer them treats from my hand from time to time. They seem to remember where they left off. In the beginning, I tried to "make" Stitch to step up and he got better, but if I missed a day in "training" he would revert to very shy again. Now that I am working with him, he expects treats from my hands, not training sessions. I could do more with target training and positive reinforcement but I don't mind Stitch the way he is. The babies I've kept have always associated me with food, so now, sometimes they'll fly off if I move too fast, but the moment they see my hands they come back for treats.
The babies are a lot less handshy, even though they were parent raised. Although I don't think linnies like hands, because my more shy of the two babies will pinch my fingers a few times before stepping on, not hard, just like "eewww, that perch is squishy
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