Yah I agree with Xavi there... It's good for the young once easier to pick up what to eat, where to poo, where to pee etc from cage mate...
Another thing is, best to thoroughly clean the cage and get rid of all smells... Then when the both smell the same, they go back to cage, the cage become a "new" place and "new" territory for them both altogether... Then better chance of getting along

As I notice my two boys, never been separated b4, whenever I clean up their cage, even without thoroughly cleaning, ie juz change all the newspapers and the towel(their base), they get back to cage as if it's brand new... run around smelling everywhere to check territory...
If after bath also no see them like that coz probably is after shock... haha
When I thoroughly clean up the cage... They go berserk and popcorn like mad... like move to new house feel like that...
This is my experience on their behaviour lo... So if two boys can get along, not too hard for two females to get along too...

.. once tercium.
. will be sworn enemy at sight.. like my timmy and teddy.
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