2) Anna didn't rely on Elsa to hold Anna's crying tears (that's the plot in Tangled, it can't be used anymore), nor did it rely on Elsa's true love's kiss (I don't know if Elsa kissed, because Elsa was back at the time. facing the audience, invisible) came alive.
The real and key reason is: Anna was able to give up her own life in order to save her relatives and let Elsa understand what true love is, and she successfully controlled her power with the true love she understood, so all The damage caused by her once uncontrollable powers, including the effect of freezing Anna as a little sister on the prairie, all recovered, so Anna came back to life. It is for this reason.
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