I think the logic here is supposed to be something like:

more knowledge = more complex brain

as you need to “store” the knowledge somewhere.

I don’t say thats how it works but i can somehow see where OP is coming from.

And he is so eager doing so. Looks like the most important task all day with him runnig up to the path. He puts everything he got into smashing that ball onto the concrete as hard as he possibly can and is all fluffed up when that thing inevitably comes down again to nearly hit him. Almost like a toddler.

Sister 1 is #7, nothing she wont gobble down Sister 2 is #8, her true form is liquid to the point you wont understand even how

How about a cat of similar age? Ask for a social one, as he seems to like to cuddle with other cats. Also maybe one with a similar activity level (e.g. a Siamese might be to much energy for yours). But in the end you know yourcat best and need to try it out.

Also think about what you want. They should be somewhat compatible, yes, but its okay for you to want a cat to play and cuddle with, too.

So decide what you need and want, trust the people working at the shelter and your gut on this one.

Good look finding your next family member.

We stopped preparing/bringing the food whenever they started getting annoying and only continued as they went silent again. First 2 times took some time, after that they learned pretty quickly that silence gets the belly full quicker. This obviously only works with regular and sufficiently fed cats. As soon as one of ours needed to go on a brief diet (stomach flu) they started to get very vocal very fast and did only turn down their volume weeks after getting fed normally again. I think shes still salty about it months later… :(

Meanwhile on my frontpage:

Please look after your cat carefully for the next few days. My vet said they can get the big C too.