Is it common to have a twin baby echeveria from single leaf cutting; could these be separated when they grow up?
And leaves of my out door aloe are turning purple instead of light green, any clue?
This answers your first question.
The question about your Aloe changing color; first of all, are you absolutely sure it's an Aloe?
This page shows you some different ones; it's important to figure this out first, because some similar plants are Haworthia which prefer less bright light and more water.
There are seasonal changes with some Aloe, do not confuse this with needing more water - that might not be what they need.
They also change color if the temperature is too cold; don't worry, as long as there is no chance of frost, they will recover as soon as it warms up.
Sorry I can't come up with any other possibilities - without a picture of the Aloe it's hard to visualize what's going on.
Hope that helps.
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