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Some examples of $\mathbb Q$-Gorenstein smoothing

I am trying to understand definition of $\mathbb Q$-Gorenstein smoothing, specially the third condition in the following definition.

Definition: For a normal projective surface $X$ with quotient singularities, a $\mathbb Q$-Gorenstein smoothing is a one-parameter flat family of projective surfaces $\mathcal X \rightarrow \Delta$ over a small disk $\Delta$, which satisfies the following three conditions:

  1. the general fibre $X_t$ is a smooth projective surface,
  2. the central fibre $X_0$ is $X$,
  3. the canonical divisor $K_{\mathcal X / \Delta}$ is $\mathbb Q$-Cartier.

We say that $X'$ is a $\mathbb Q$-Gorenstein smoothing of $X$ if there exists such an $\mathcal X$ and $X'=\Psi^{-1}(t)$ for some $t\in \Delta$.

For example, I am trying to understand the following.

Q1: Let $m$ be fixed integer such $mK_{X_t}$ is Cartier for every $t$. Is there any example where 3rd condition is not satisfied.

Q2. If the total space of the family is $\mathbb Q$-Gorenstein then is it true that 3rd condition is satisfied.

Moreover, is there any reference with examples to understand this.

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