Sorry, long post.
We worked very hard to ensure our girls never knew my mother was more generous with my brother’s kids. My girls would have been happy with hair bows from CVS, but the other two got carefully picked books, games, and checks.
I didn’t mind that, my own grew up to be generous and kind, while his (still teens) are seriously struggling with life itself. What was hard was all those years when my mother insisted he deserved or needed more, when she didn’t realize he earned more than double what we did (Let’s just say, they’d be college full pay.) (I was sworn to secrecy and he was always complaining to her about money.) Even when his career field went bust, he had assets accrued that could generously support his family. Even years later, those assets are still there.
When the time came, I split my grandmother’s estate 50-50 with him. And same for my mother’s. Neither had wills. My kids will inherit my/our assets equally, but owing to D2’s financial idiocy, D1 is executor, at this point. (Small family, no other relatives or friends in a position to manage this. Both girls understand and I trust D1 to make the decisions that work for both of them. We’ve had frank talks. Plus the writing in the will covers decisions.)
But on an ongoing basis, which is what I think @oldfort is after: D1 (in a corporate position) out earns D2 (in a noble people-helping field.) Both work hard, take work seriously. That and their good natures are what matters to me. D2 has begged car payments and more, until recently. It’s easy to free-will gift D1 something, or offer, since she almost never asks and does offer to pay back. (Eg, I paid the deposit on her lease car, she paid me back.)
Vacations. I pay the bulk, they contribute. Eg, I pay the house rental in Maine, a meal if we dine out, and they and their partners do all the main grocery shopping, split that. If we venture off to visit DH’s family, for pleasure or a wedding or funeral, I pay hotels, a main meal, they pay for a few meals. It’s at the point where they offer this, when the check comes.
D1 gifted me with our tickets to Ireland, I paid hotel and our more expensive incidentals, but she was just as forthcoming when splitting or paying for a dinner or the airport transport. Yes, D2’s nose is out of joint, but she couldn’t afford to come along, the two girls discussed that in advance. And no, at this point, D2 won’t get a gift equivalent to what I paid there, for D1. Will I “take” her someplace for “Mom and Girl time?” Sure. But not at that level. Not at this point, when she isn’t managing money well. That’s not “tough Mom.” We’re close, but the history of bailing her out, since college, is still fresh. It’s multi times what D1 has gotten.
This issue will arise again, as we all want a Christmas vacation, partners included.
Some have said here, “Fair isn’t always equal.” But the full expression adds, “And equal isn’t always fair.”