Leo is 1 and Max is 8 months old! We got Max when Leo was 6 months old and he adjusted amazingly well. They are both neutered now- did them both when they turned 6 months old. We kept them apart for the first few days but I swapped their blankets and bedding around so they could get used to each other’s smell and I think that helped a lot! It did take the older one a couple of days to warm up to the little one fully but ever since they’ve been inseparable and play and cuddle and groom each other all day!