To be honest, I kind of expected them to be HIV positive but the background story definitely took my breath away right now. And maybe you're not thrilled with this chapter, but I think it's pretty good to put in 'an adult chapter' alongside the adorable child's ones :)
I think it's safe to say that this is the cutest beggining of a story I've ever read! And also pretty original because even if there are other stories starting with how the girl became a friend with one of the boys when they were both small, it's never this detailed and I already love it! Keep the great work because I can't wait to read more :)