Demon Slayer shenanigans and incorrect quotes

if Kibutsuji's daughter is half demon does she have any cool abilities?
can someone be born as a demon?
if a demon and a human have a kid could the child be a demon?
can two demons have a child?
if demons burn in sunlight what does Kibutsuji do when it's daytime?
what happened to the rest of the spider demon family that was shown in the sister's flashbacks?
why did Susamaru lie about being a member of the twelve kizuki?
how strong is Muichiro if he's a pillar that's only 13?
how important were Susamaru and Yahaba to Kibutsuji?
how come Rui didn't die when Tanjiro cut off his head?