You already know the pattern. You paid the pharmacy copay on your card because it was faster than calling anyone. You covered the grocery run, then the co-pay for the aide's extra hour, then the mileage to the appointment across town. Nobody said no. Nobody wrote anything down either. Now it is three months later, the group text is full of questions about the total, and you are the only one who can tell what was paid, when, and for what. That is the moment to set up the ledger, and the best time to set it up is before the next charge clears.
Local option: New Plan Care gives families in the St. Louis area in-home help so a parent can stay home: companionship, help with bathing and dressing, meals, and overnight care. Call (314) 405-0887.
Decide what goes through whose hands
Start with the simplest question: which account pays for what. Money for Mom's care can come from her own income, from her savings, from a joint or shared arrangement among the siblings, or from you personally. Each route leaves a different trail. Ask yourself whether the bill is in her name, whether the statement comes to her address or yours, and whether you have the login to see it. If you cannot see the statement, you cannot check it, and you cannot prove what you paid.
Check the bills that come on a schedule first. Rent or a mortgage payment, utilities, insurance premiums, a standing care invoice. These are the ones that quietly double up when two people pay the same month without knowing it. Put each recurring bill on the list with the name of the person who pays it and the day it goes out.
Build a record that anyone can read
A ledger does not need software. It needs the same columns every time. For each payment, record the date, the payee, the amount, who paid, the account it came from, what it was for, and where the receipt lives. A photo of the receipt in a shared folder counts. A card statement with the line highlighted counts. A note that says paid the aide, $ and the word cash does not count, and you will feel that gap at the worst moment.
Keep the care costs separate from your own costs. Mileage, supplies you bought for her room, a meal you bought while you sat with her at the clinic: these are real, and they are part of the labor you are carrying. Put them on their own line, with the reason written next to them, so the siblings can accept or question each one on its merits instead of arguing about the total.
Agree on the repayment rule before anyone needs it
This is the part families skip, and it is the part that causes the fight. Before the next charge, get agreement on four things, in writing, even if the writing is a text thread that everyone replies to.
First, what counts as reimbursable. Care costs for Mom, yes. Your gas to visit on Sunday, maybe. Your gift to her, probably not, unless it was agreed. Second, how often you settle up. Monthly is common because it is easy to check. Third, what happens if a sibling cannot pay their share this month. Does it roll over, get split later, or come out of Mom's money first? Fourth, what happens to any balance that is still open when care changes or ends. Without a rule for that last one, the ledger becomes a debt nobody can collect.
Ask each sibling to confirm the rule by replying to the thread with a plain yes. You are not asking for a contract. You are asking for proof that the person who agreed to split the cost also agreed to the way the split gets counted.
Check your own exit
Before you commit more of your own money, ask what happens if you stop fronting. Who takes over the next bill? Does the ledger stay open so the old charges can still be settled? Is there a date when you hand the card back, and does someone else know which account the next statement goes to? A plan you can leave cleanly is a plan you can keep up for the long haul. A plan that only works if you keep paying is not really a plan. It is the pattern again.
If the numbers are getting too big for a spreadsheet and a group text, that is a sign to bring in outside help to sort the money. Our local help page lists where to start in the St. Louis area, and start here explains how this site approaches the questions. The ledger is your record of the labor. Keep it honest, keep it shared, and the next conversation with your siblings gets a lot shorter.