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<p>Then why did you bring the step D into the discussion at all? Seems to me that she is completely irrelevant to the situation with the GPs. There are 4 kids here. We know 1 has good grades and 1 doesn’t. The other two could be all over the map. Since when are children in a family all cut from the same cloth, academically or in any other way? The only thing her situation bears witness to is the character of the OP, who is apparently willing to support her and send her to school, without the assistance of her bio father. </p>
<p>I would suggest that you refrain from attempting to psychologize. My in-laws were both dead by the time my S was ready for college, and they certainly would not have been able to afford to contribute substantially had they been alive. They weren’t my favorite people, but I certainly wasn’t burning with resentment, either. (At least, not most of the time. 
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