The fortune teller said that I was a boy of Guanyin and my daughter-in-law was a boy of Tathagata.

Obviously, this is nonsense. There is no Buddha in Buddhism. It's just a name created in Journey to the West. Where did you get a boy who didn't? Moreover, many people are called boys around Guanyin by fortune tellers or great gods. If you go to Baidu, according to him, how many boys will be around Guanyin? There must be tens of thousands or hundreds of thousands.