Is the other older cat a male? if so it could be a domaniate thing My friend has a older cat that is male and he is sweet to everyone exept her husband the cat trys to play the dominate male in the house'

My guess is that the younger cat is used to having the older cat as a companion. When that companion is gone, your younger cat probably gets a little lonely and possibly even feels a bit insecure. If that's the case, he's staying near your boyfriend for company and to keep from feeling abandoned. It's even possible that he's figured out that you and his kitty companion always come back to where your boyfriend is, so he sticks close to make sure he won't miss your reappearance. Let me give you an idea about how much feeling abandoned can matter to a cat. Some years ago I had a single indoor cat who was always very unhappy if I was gone for even one night. When I got back, he would make a huge fuss and demand to be petted and loved and reassured that I was really back and wouldn't go away again. However, once I got a second cat, that changed. The first time I was gone after he had his companion kitty, I was gone three days and two nights. I got home and was worried when he wasn't waiting for me right inside the door to give me what-for. I went looking and found him sleeping near his new friend. I spoke to him, and he barely opened his eyes and gave me a look that plainly said "oh, were you gone?" A cat who has been well socialized can be sensitive to his people or his kitty friends going away. I think that's what's going on with your younger cat.

i would think that me being cat would wanna spend time with another cat that i can run around with and wrestle.. especially if i dont see the other cat that often.