Lord Hooke AB+no Fr, Lady A+no,Helen A+no,Roule O+no,Henry ?,IdaA-,Ann B+,Tom O- no,Jane A+,Beth O-,TinaA+yes?

Question

As a bolt of lightning flashed above Black Mourning Castle, a scream echoed from the den of Lord Hooke. When the upstairs maid peered through the door, a freckled arm reached for her neck. Quickly, the maid bolted from the doorway, locked herself in the library, and telephoned the police. Inspector Holmes arrived to find a frightened maid and the dead body of Lord Hooke. Apparently, the lord had been strangled. The insepctor quickly gather evidence. He noted blood on the ltter opener, even though Lord Hooke did not have any cuts or abrasions. The blood sample proved to be O negative. Some of the family members were deeply tanned, so it was difficult to determine whether or not freckles were present. Freckles = dominant. The detective explained that one of the heirs to the fortune was not Hookes biological child and that the child commited the murder. Who was the murderer
Pedigree
1. Lord Hooke - Lady Hooke
2. Tom - Jane Helen - Roule Ann Ida
3. Beth Tina Henr

Answer 1

This is kind of confusing, so lord & lady hooke have three kids? Who's kids are the third generation?

Anyway, if lord hooke is AB+ and lady hooke is A+, none of their kids kids can be O. They could only be A, B, or AB..
Maybe I misunderstood the question..