Monkey see, monkey do (Smartoonz)
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"Monkey see, Monkey do" is a game in which one kid is "it", and everybody else is "the monkey". What monkey sees, he does, so everybody has to imitate what the "it" person is doing.
We also use the expression "monkey see, monkey do" when we want to tell someone that they lack character (they don't have personality) and they just imitate the bad things other people do.