Simon was a family friend of your sister so you always known him, when you’ve found out that he and your sister had an affair and that your nephew was in reality Simon’s son and not your brother in law’s, you two grew closer, since your sister didn’t wanted Simon near his son Ben you secretly brought the kid to him so he could see him, that’s how you two ended up together, for now behind everyone’s back especially your sister, you now knocked at his door with Ben, he went and open “Hey beauty”