ReferenceError: babyTailTimer is not defined

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    this.babyTailTimer = 0;
    this.babyTailCount = 0;

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    var babyTailCount = this.babyTailCount;
    ctx1.drawImage(babyTail[babyTailCount], -babyTail[babyTailCount].width * 0.5 + 23, -babyTail[babyTailCount].height * 0.5);