Clea and Babette are the same, only it involves two brands of kitty milk.
Clea tends to push her sister out of any food. Babette doesn't seem to mind all that much when Selina is in the bowl. In fact, she often will walk away from it when her sister is no where nearby and it is clear drinking.
On the other hand when there's whiskas she will lick the bowl clean.
Feline brand loyalty.