This is a fairly good quality video of two Bettas spawning and spitting eggs into the nest. The female looks dead after laying the eggs. It obviously takes a lot out of her. She seems to be trying to help him spit the eggs into the nest but not doing a great job. ;D Both fish have major fin damage presumably from the "courtship". Interesting process but I could NEVER put any of my babies through this. I've heard that the male sometimes dies shortly after raising the fry from exhaustion and stress. I'd never want to risk losing any of my fish kids.
Niles seems to want to be a father and he builds a bubble nest EVERY day in one corner of his tank and every morning it's gone because the filter blows it apart. I bet he and my marbled/grizzled female Angel (below) would make some beautiful babies but I'd never risk it.