For federal purposes, the winnings of $900 are reported on the 1040, Line 21, and the losses up to the amount of winnings, $900, may be claimed on Schedule A under Other Miscellaneous Deductions; the remaining $40 may not be claimed.
half-sister - a sister who has only one parent in common with you. half sister, stepsister. sis, sister - a female person who has the same parents as another person; my sister married a musician.
For half-siblings, they only share one parent, whether it is their mom or their dad. So two siblings with the same mom have different halves from their dads and two siblings with the same dad have different halves from their moms. But either way, they are half-siblings.