Money advice: My parents gave me and my sister money to make the downpayment on our houses. Now they've given my sister another big gift. It's not fair!

Pay Dirt is Slate’s money advice column. Have a question? Send it to Kristin and Ilyce here . (It’s anonymous!)

Dear Pay Dirt,

My sister and I (both in our 30s) are very different. She’s brilliant, accomplished, and a high earner. She has a loving husband who earns even more, and three wonderful children who I adore. I’m fairly smart too, but I was born with a medical condition that has prevented me from starting a family or achieving a similar level of success as my sister. That said, I have a comfortable salary, and I love being an aunt to her kids.

Our parents are not rich, but are very supportive and generous with the money they do have. They are also a little odd, and their financial support usually comes with a caveat. They have always been concerned with treating us