The photos and comments of his son took advantage of him, saying that his son looks like him. How should I reply?

There is a comment in your son's photo that your son looks like him. Then don't get used to this bad habit. It's best to say under his comments that your son actually looks like yourself. And say, well, then you're just like me. Your son is like his father. Or your son can be like his grandfather, in which case he won't do anything. For this kind of person who likes to take advantage, it is really time to go back. If you don't argue with him for a long time, he will push his luck again.