Meeting of the young family heads

Young Integra Hellsing has just lost her father at the young age of thirteen. Having just survived the assassination attempt by her uncle and awakening alucard in the basement, she struggles to run the hellsing organization in her young age. The queen hearing of Integra's difficulties makes a request of her most loyal guard dog, who also had to take over his family estate and occupation at an early age with (unknowingly to the queen) a supernatural servant.

I know black butler takes place in the 1880s and hellsing in the 1990s to the 2000s, but for this au/ crossover, let's say black butler takes place in the same era.