1. This baby must be from Wang Yadong.
2. It was because Xiaoxiao was found pregnant that Wang Yadong's conscience was really awakened. He had been in the army before, and the two broke up.
3. Xiaoxiao and Wang Yadong live together, and so on. The evidence shows that the child must be Wang Yadong. As for the final outcome of Tang Xinyi, because she became a vegetable, at least she saved her life.
Therefore, he will definitely not abandon and reunite with Xiaoxiao. The best ending is that his Chen Guang awakened Tang Xinyi. As for whether they are together as they wish, there are variables.