Eh I know this is unpopular opinion but I think he’s Pierre’s. I know all the dates and locations and resemblances and ideologies line up to support the Castro theory, but Fidel had dark, dark brown eyes. Justin has blue eyes. Not hazel or dark gray blue but true blue. That’s a recessive trait that usually requires two light-eyed parents to pass down. Plus if you look for images of young Pierre you can see the resemblance better. There’s one in particular of Justin as a kid at a baseball game with Pierre and their smiles and profiles are exact, especially the way their cheeks bunch up high on their faces. The resemblance became hidden as Pierre got older. It doesn’t help that Pierre, Margaret and Fidel all share similar long, pointy noses, wide expressive eyebrows and full bottom lips, but you can’t fake the dominant/recessive gene expression.