I have lost some rats this year due to different things. I also lost remmys cage mate Loki who as been with remmy sense i got them. Remmy is two years old and he seems to have done a 180 after losing him. he seems like he is depressed and is not as out going as he used to be and likes to sleep a lot also he will not have anything to do with my brother now and the only thing we can think of is that he was the one to remove loki when it happened. Even when he's out he just sleeps with me instead of running all over the place and getting into trouble like he use to. Now what i am curious about is weather i should just keep him by him self or if i should get another rat. also if i get another rat would a younger one be better then a older one or should age not really matter?