He did it.
Dad fixed the bathroom light.
I don't know what it entailed, whether he had to harness the powers of darkness, pledge himself to Cthulhu, or just look up a video on YouTube, but Dad replaced the bathroom light switch, and it works.
I make fun of my dad a lot, mostly because he deserves it (also because it is so blasted fun), but seriously: He CHANGED THE LIGHT SWITCH. He did it in one day. He was not injured. No one else was injured. And there is nothing new wrong with the bathroom after he worked in it. This is groundbreaking. It is amazing. And he deserves praise, plus a gold star and also maybe a fancy coffee.