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.
(The same status as a sibling who is of both the same father and mother as you.) But if you share the same mother but have a different father, he is only considered a half-brother and has a different halachic status.