Hello, I'm looking for advice. I have two rats for just under two years. I bought them both at the same time. Suddenly, one of the rats was acting strange last night and after contacting an emergency vet, I had to get him put down due to ilness. This is very sudden to me and I have been upset all day as both rats seemed healthy. However, this has left the other alone and I don't know what to do to comfort him when he is grieving. I have moved the cage into the bedroom and I bought a soft toy to comfort him. I know that rats need companionship but I don;t know how long he might need to grieve etc. Any advice?