Responses

Yes, only because of the story to which the MC reincarnated in. The MC's son (Hyeol) and the ML's son (Kotsu) are supposed to end up together in the original story but in the present time, the MC's son have a crush on another child, the MC's friend's child (Jeonghan). So instead of being the ship, they end up being rivals for Jeonghan.
I've finished reading this one and we're so near to it in here.
For those who are worried about whether who will end up with who, here's a spoiler for you
--- Hyeol and Jeonghan is the ship and will probably end up together only if the story continues
--- Both fathers end up together