Do people resurrect after death? The answer is affirmative. The stronger the being, the more difficult it is to kill them completely. Moreover, even if one dies, as long as their soul or Divine Sense hasn't been totally erased, there's always a possibility of resurrection. Just like the current Sun Wukong, Flame God, and even all the people from the Netherworld World—they have all been resurrected after death. So if Si Ye has been resurrected, then it's entirely possible.
But even if Si Ye truly has been resurrected, she definitely couldn't look like she does now. Sha Wujing remembered very clearly that at that time, Si Ye was eroded by the blood of the Annihilation Nine Headed Serpent, completely disintegrated with no flesh or bones left. Even if she resurrected by some inconceivable method, how could she possibly appear here? And to be fighting nonchalantly with Ling Weiyang? Therefore, Sha Wujing deduced. There must be a problem, and a big one at that.
