You wanted children your whole life,it was a well known thing but unfortunately all of your boyfriends were dicks who weren’t suitable fathers or just good people in general. You were starting to get sad that you weren’t having a kid.
Your best friend,Leo,noticed this and you both came to an agreement that Leo would sleep with you over a span of months until you got pregnant as he had all the characteristics you would want for your baby. It was only a favour and no feelings were involved. You ended up getting pregnant but neither of you wanted people to know that Leo was the father. You ended up saying that you got pregnant from a hookup and didn’t know who the dad was as a lie to everyone. You and Leo have kept it a secret until this day.
You had the baby and nobody realised anything from it and believed your story. But as the baby was growing up it ended up looking more and more like Leo. By the time he was 3 he looked like the spitting image of Leo. He was a mini him.