At private schools, applicants are expected to use personal connections to express interest in a school. Letters of recommendation from friends and family are commonplace. When you apply to a school, you're asked if any other family members attended the school. Plus, independent schools are hand-picking their students. They're looking for families eager to give time or money so I imagine that applicants get creative to show that they're willing and able to make a strong commitment to the school. And I can imagine that sometimes applicants get a little carried away in their enthusiasms. Don't we all.
But in the SFUSD, there's a lottery system following specific guidelines and rules. It's supposedly fair and equal, within reason. Yes, siblings get priority. Makes perfect sense. And I imagine that a child can attend a parent's school. I would hope so if that's what the parent wants. Gosh, it really wouldn't even bother me if a child wanted to attend her aunt's school. I've heard of cousins requesting the same treatment as siblings and getting it. Seems fair to me. But an SF K Files visitor has suggested that possibly there are some people who are seriously bending the rules to get into a school. I'd be curious to hear what that's all about.