My rat Kenny was given 2 me as a baby. He is about 4-5 months old now, very playful and affectionate, and I would like to get him a friend. I have read that it is the easiest to introduce a baby male to another, older male. My concern is that by the time quarantine is over, the baby will not be so little anymore. Has anyone else had success with introducing a baby male to an older male? Any suggestions?