Perfect! Everytime my feral is purring at someone, I open the cage door and stroke her with my back stratcher. then, after a few of those, I reach in and replace with my hand- she notices the switch but as long as she's focused on her "loves" she keeps purring! It's a start! Without the cats around to distract her, she spits at me when I approach her still... (though I don't think I need the back scratcher anymore!) Do you have a ruler or something you can use? lots of times they will lean into something like that when you use it to rub their cheeks and start the purring.
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