The great sage, his wife

A long time ago when he was on the journey to the west, he met a young girl that he fill in love with her name was Y/n he made promise to her, that when he gets back from his journey, he would take her with him so they could be together. She was happy with that and agreed, so when he came back from his journey after they picked up the scrolls he took her with him. He took her back to flower fruit mountain where she would be safe. She stayed there with him for years until she was around 26. That's when he decided he wanted her to be in mortal with him. So he proposed an idea that they should get married. She was a little hesitant at first, but once he brought up and he can make her more so they could stay together. She agreed.

Years later tragedy struck the great sieges wife and son disappeared he didn't know where she and their son went, or if they was safe as he went to find her.

What happens when he finds her and finds out what happened to her.