Yes 6 weeks is too young. You can ask a vet but when the time comes you can have it done through Sicsa. I had 3 of my animals done there and I was happy with what they did.
A kitten that young is not grown enough to be developed. It has to grow more, I am guessing that the cats must be at least 6 months old.. or older. I think they should be allowed to get to just about ready to go into heat first, but then I would Recommend that you call the shelter First. And a vet.. to find out current information 🤔
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