I'm admittedly looking at it from a different angle, but I think it's still relevant. Even if you're focusing on performance metrics and I'm looking at evonomics.
The big 5 marketing target events: graduate, marry, buy house, get pregnant, retire. All events proven to change spending habits.
Having a baby often means moving into a bigger space.
The market isn't "housing", so it's not appropriate to consider differences in 3k between someone having a child vs someone not having a child.
It's "housing suitable for singles/couples expecting their first baby", etc.
So you are differentiating (sub)markets, but not necessarily the individuals within.
Similar to how brides planning a wedding aren't competing in a national market, but find themselves competing with a dozen or so other couples all essentially trying to plan the same wedding.
But with the extra money at childbirth, the more likely sink for the competing funds (in the US) is going to be daycare and then preschool.
That is, if it's not finding a bigger home that's more child-friendly. Which is similar to the wedding thing. Available properties near work, within budget sets a sub-market. Then it's just bidding for who gets the nicer home on the park with the better school.
You already see this with hud section 8, where apartment complexes especially set their lowest price at the maximum govt reimbursement rate. Similar situation in college towns where off campus apartments and neighborhoods fluctuate based on dorm rates and allowable student loan amounts.
And slightly nicer but older single family homes set their prices slightly to moderately higher, because as a sfh landlord, you don't need 50 renters, just 1.
But the situation is similar, where a large number of individuals in a particular submarket are all being provided with equal or at least very similar "allowances", and the market finds both monetary and non-monetary ways to adjust and differentiate individuals within.