"terrible twos" meaning in English

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          "ref": "1988 February, Working Mother, volume 11, number 2",
          "text": "The terrible twos can begin at 18 months and last until about age five.",
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          "ref": "1990, Susan Hughes, Ryan: a mother's story of her hyperactive/Tourette syndrome child",
          "text": "The terrible twos came early. Almost a year early. When Ryan learned to walk it was the end of our peace of mind!",
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        "A developmental stage in toddlers, normally occurring around the age of two, involving refusals and temper tantrums."
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        "(informal, psychology) A developmental stage in toddlers, normally occurring around the age of two, involving refusals and temper tantrums."
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  "word": "terrible twos"
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        "A developmental stage in toddlers, normally occurring around the age of two, involving refusals and temper tantrums."
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        "(informal, psychology) A developmental stage in toddlers, normally occurring around the age of two, involving refusals and temper tantrums."
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