In the beginning, the smoothie and milkshake were still spatially separated and could only sniff through the crack in the door. In order for the fur noses to perceive the smell of the other cat as positive, they were fed near the door that separated them. Later they could smell and see, but not touch, because they were separated by a grate.
That was a good thing, because at the beginning smoothie reacted with an outraged hiss to the family growth. But little by little the kitty got used to each other and overcame their caution towards each other. In the meantime, they not only tolerate each other's presence, but also clean each other, cuddle and play together. What a nice cat friendship!
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