A new addition, what fun!

It takes time for them to adjust, anywhere from 3 to 6 weeks. What you are describing is a normal reaction - by both of them.

When I bring in a new one, that one sleeps on my bed with me - with the door closed and the others outside in the rest of the house. I hate doing that to the exisitng kitties, as they are used to sleeping with me during the night. But I need the newbie to bond with ME, and especially a young kitten. I want it to know that I am here for it and it can come to me. It can rely on me to take care of it.

Depending on the size of the kitten and the way the personalities are going, this may go on for a week. I find that having all of them in with me at night happens BEFORE I can trust them together during the day, especially if I am out at work. They all learn that, when I am present, there WILL be peace!

When Chestnut arrived 8 years ago, he was just a little 1 pound sickly kitten. So he slept in the carrier on my bed with me, and after the first night, I let the others come in and sleep on the bed with me and the carrier.

Hope this gives you some ideas to consider.

Getting the opposite sex was the right way to go! Now start enjoying the new little one, and the positive interactions between the 2 will happen in a VERY short time.