Luck wished....

Truly it sounds as if all they need is time. You might talk to them about getting along. Whether they understand words or tone or body language, sometimes verbalizing the behavior you want helps it happen.

(I remember once I had a dog and a cat I thought would never be friends...fought and growled... for weeks. Finally I'd had it. The cat was upstairs growling the dog was on the main floor growling and I was on the stairs crying because I thought somebody would have to go. Swear that within a few minutes the cat came down and started licking my cheek, the dog came up and started licking the other and that was the last fight.)

Cats are very aware of body language and subtle status cues. You are probably right on target that they are starting to want to be friends, but being wary.... Think of sixth graders at a dance. Who will be the fisrt to cross the great divide and ask the other to dance.....