Parent FAQ

A family “bank” where your kid earns, saves, borrows, and sets goals with pretend money you keep track of together — so they learn how saving, interest, and trade-offs actually work before real money is on the line.

No, and no. Cairn never moves real money. There is no bank connection, no debit card, no payment rails, and no way for the app to touch a real account. It is a shared ledger — a scorekeeper for money you and your child settle between yourselves, however you already do that.

That’s a deliberate design choice, not a missing feature. It removes the entire category of risk that comes with giving a child a payment instrument, and it keeps the focus on the lesson.

Two places. Internal accounts (spending, saving, goals) are tracked by Cairn as your child earns and allocates. External accounts — a real 529 or brokerage you want your kid to see grow — are snapshots you type in whenever you check the real statement. Cairn never logs into anything on your behalf.

It was built for a 9-year-old and grows with them. The kid interface adapts its wording by age, and the lesson content ranges from “what is saving” up to compound growth and borrowing costs. Younger kids will need you alongside them; older ones can run it themselves.

You create chores (one-off or repeating). Your child marks one done, and it waits for your approval — nothing credits itself. Approved work accrues earnings.

When there’s money to pay out, your child decides how to split it across their accounts and sends that plan to you; you approve it. They practise the decision, you keep the final say.

No. A child can never approve their own chore, change an account balance, or alter a loan. Those are parent-only actions, and that boundary is enforced in the database— not just hidden in the interface. Even a modified browser can’t get around it.

The one thing a kid can change on their own is cosmetic: their Cairn Buddy avatar. No money involved.

The ledger is append-only: a posted entry is never edited or deleted. Corrections are new reversing entries, so the history always shows what really happened and when. It behaves like real accounting, which is part of the lesson.

Because borrowing is the money lesson kids are most likely to learn the hard way later. A Cairn loan is pretend, but the math is real: your child sees the payment schedule and exactly how much the interest costs them in total.

You originate every loan and set the terms. Nothing borrows automatically, and your child cannot change a loan.

Borrowing also starts switched off: every kid’s borrowing limit begins at zero, so the feature simply isn’t available until you deliberately raise it.

One thing: the optional monthly chore bonus. If you’ve set bonus tiers (say, 100% of repeating chores done earns $20), that bonus is credited automatically once the month is scored, rather than sitting in your queue. You control whether it exists and what the tiers are; leave them empty and nothing auto-credits. Everything else — chore rewards, payouts, lesson rewards — waits for you.

No — and this one is worth understanding.Cairn does not pay interest into a child’s savings on a schedule. Balances change only when real activity happens: earnings, allocations, goal contributions, purchases.

The growth percentages you see are used for projections— the “what could this become” view — not to credit money. If you want your kid to actually receive interest as a lesson, pay it yourself as a deposit so it’s a real, visible decision.

An optional house rule: a minimum percentage of each payout that must go to a long-term account before the plan can be submitted. You set the number; the app holds the line so you don’t have to re-litigate it every payday.

They are illustrative teaching numbers, not forecasts. The Time Machine and the projections next to each account exist to show a shape — money left alone in a growth account for years can become meaningfully more — not to predict your returns.

Every screen that shows a projection carries that reminder, and the numbers are presented as what money could become, never what it will. Nothing in Cairn is investment advice.

No. Your child signs in with a username and a PINthat you set up for them. Cairn never asks for a child’s email address, phone number, street address, or date of birth — only a birth year, which is used to pitch the wording at the right age.

Behind the scenes each kid account needs an internal identifier that looks like an email, but it’s synthetic, points nowhere, and can never receive mail. There is no inbox attached to your child.

The PIN is stored hashed, never as plain text — nobody, including you, can read it back out. To reset it you set a new one rather than recovering the old.

Guessing is rate-limited: 5 wrong PINs within 15 minutes locks that username for the rest of the window. The limit counts attempts against unknown usernames too, so it can’t be used to work out which usernames exist. Resetting the PIN as a parent clears the lock immediately, so a locked-out kid is never stuck waiting on you.

PINs are 6–12 digits, and obvious ones (1111, 123456, and similar) are rejected when you set them.

Go to Kidsin the parent nav and reset it. You’ll set a new PIN, which also clears any lockout. There’s no need to recreate the account or lose any history.

Yes. From Kids you can download a complete JSON exportof that child’s records — their accounts, ledger history, chores, goals, lessons and reflections, and rewards. It’s the whole file, not a summary, and the request itself is logged.

Yes, from Kids. It removes their sign-in, their profile, and their personal records — chores, goals, loans and lesson work all go with it.

One deliberate exception, so you know exactly what’s kept: the ledger entries stay, because they’re your household’s financial history and the ledger is append-only. Their name is detached from those rows — the account is relabelled “Closed account (former member)” — so no child’s identity remains in what’s left.

Yes. As the household owner you add them from Kids by entering their name, email, and a temporary password you pass to them yourself— Cairn doesn’t send an invitation email, so nothing about your household goes out over mail. They sign in at the normal parent page and can change it after.

A second parent gets the same day-to-day abilities you have— approving chores, payouts, loans and rewards, and full visibility of the household’s money. Only the owner can add or remove parents. Removing someone revokes their access immediately while leaving the approvals they already made intact in the history.

Yes, using any authenticator app. Setting it up is optional — but once you enrol, it’s enforced: a session that hasn’t passed the second factor cannot reach a single parent screen, not just the sensitive ones.

Worth doing. The parent account is what approves money decisions and can reset your kids’ PINs.

Use Forgot your password? on the parent sign-in page. We email a link that works once and expires after an hour, then you pick a new password. You can also change it any time from Kids once signed in.

If you have two-factor set up, you’ll still be asked for your code afterwards — resetting a password is not a way around 2FA.

Only if you turn them on — they use your browser’s own permission prompt, so nothing is sent until you allow it. When enabled they cover the things that need you: a kid marking work done, cash they’ve logged, and payout plans waiting on approval.

Cairn installs from the browser — on iPhone use Share → Add to Home Screen, and on Android/desktop Chrome use the install prompt. It then opens like a normal app, full screen, with its own icon. There’s no separate App Store or Play Store download.

Not yet — Cairn needs a connection. Balances and approvals are worked out on the server so that two people acting at once can never end up disagreeing, which is the right trade for money, but it does mean an offline device shows nothing. Installing it to your Home Screen makes it feel like an app; it still needs signal.

New households start with a 14-day free trial, no card required. Current plan and pricing details live on the Billingpage in the parent nav, which is also where you’d manage or cancel.

None of the three.No advertising, no analytics or third-party tracking SDKs, and no social layer — no feed, no friends, no messaging, no way for your child to be contacted by anyone. There is nobody else in your household’s Cairn but the people you invite.

In one place: the daily market newsbrief, a short kid-safe summary of what’s happening in the markets. It’s written by an AI model with web search, then filtered, and it’s explicitly instructed to avoid predictions, buy/sell suggestions, and alarming language.

None of your family’s data goes into it.The only input is the date — no names, balances, goals, or activity. One brief is generated per day and shared by everyone, so there’s nothing personal to leak. If no AI key is configured the app falls back to a built-in library of evergreen explainers instead.

The buddy’s “Ask my buddy” explanations aren’t AI at all — those are written from your child’s own numbers on your device.

No. Every household’s data is isolated at the database level, and that isolation is covered by automated tests that specifically try to read across households and must fail. There are no leaderboards or cross-family comparisons anywhere in the product.

Only what you choose to put in. Cairn shows a child their own accounts and any external balances you deliberately add for them. Your salary, household budget, and any account you don’t enter simply aren’t there. There’s also a one-tap privacy toggle that blurs every dollar figure on screen — handy in public.

The kid app is built for that: balances start hidden on every single load, and a tap reveals them. It re-hides next time — there’s no “stay visible” setting to forget about. On your own parent screens the toggle remembers your choice instead, since you’re usually not on a school bus.

Reference rates and account rules aren’t baked into the app — they live in Rules as dated versions that you enter and can review. That includes the federal reference rates used as a teaching benchmark for family loans, and the contribution rules for newer account types.

Once a loan is created it keeps the rule that was in effect that day. Adding a newer rule version never silently rewrites an existing loan — which is both how real agreements work and the only way the numbers stay explainable months later.

No. Cairn is an educational tool. Nothing in it — including the calculators, the projections, and any interest-rate reference material — is financial, investment, tax, or legal advice, and none of it is personalised to your situation.

For decisions about real money, real accounts, or anything with a tax consequence, talk to a qualified professional who knows your circumstances.