Can you separate two stray male kittens?

Okay, so my aunt brought over two stray male kittens that are siblings and were found together. My mom picked out one and not the other. Now the one we have sits in the middle of the kitchen and meows all night. If anyone could please provide any scientifically proven data where it would be unwise or unhealthy to separate them that would be much appreciated.

Also, just to clarify, I'm asking this question so I can show to my mom to convince her to either get the other kitten or either reunite him with this brother.

[we have only had the kitten for three days]
Below is a picture of him, I took if with my iPhone so the quality may not be the best.

Aw so cute! I volunteer at the humane society. There, they have cages of cats and in some of the cages there will be two kittens/cats that grew up together. When cats are really young I think it's ethical to separate them and give them to different owners but in your case the kitty looks older and has probably bonded with his sibling and is now in pain. He doesn't know where he is or where his sibling and only connection is. I would definitely recommend getting the other cat.
My family used to have a male and female cat, and they were siblings. They grew up together so we bought them both. They would sleep cuddled up with each other and they stayed together for years. When the girl died, our other cat was devastated. We didn't show him the body, so he didn't know where she was. He was obviously distressed, wandered the house, meowed a lot, slept little. We would see him walking off into the woods alone and he always tried to slip around our feet to squeeze through doors to places he wasn't allowed in. We hadn't observed any of these behaviors before, so it was very sad for us to watch him go through this. Never separate siblings.

Yes, you can. Cats do not have the same concept of family as humans do - they fact that they were siblings is not significant. Cats are separated from their littermates all the time -it's the natural way of things. Breeders, accidental litters, shelters - all separate the kittens. Even in the wild, with feral cats, the litter is driven off so that they don't inbreed. If it were true that you can't/should not separate siblings, how would anyone even get a pet, and how could you account for the millions of well-adjusted cats who were separated from their littermates at the proper age? The kittens miss having a playmate - they are not pining for their brother. They will do just fine on their own.

Personally I would take the little guy to bed with me and cuddle him up. He is just lonesome and a little scared right now. Their life changed a lot in just a short time. By the time you convince your mom of anything, he will be over it.
Love him up, brush him(to mimic being groomed by his mom) cuddle him. He will be fine.

The cat will get over it in time.

It would be better for you and the cat to be together with it's brother, i have 2 cats and when one of them is away the other one meows like crazy