AITA for telling my sister to buy her own pads after she использes all the household supply?

I (19F) stockpads for our house because my periods are irregular, but my older sister (23) — who lives at home, works full-time, and has regular periods — repeatedly uses the whole supply without telling anyone. I told her to start buying her own and we had a big argument — now I’m wondering if I was wrong.

I’m 19, a full-time university student with a casual job, and I live at home with my family and my older sister (23). I usually buy the pads for the house and keep multiple boxes on hand because my cycle is irregular — sometimes it only comes every two months. My sister gets her period regularly every month and works full-time, so she uses them more often. I do most of the small grocery runs during the week (my mum drives me), while my mum does the big weekend grocery hauls. Despite that, each time my period finally arrives the cupboard is empty because my sister has used all the pads and never says anything when the supply runs low.

I buy and stock pads because my periods are unpredictable; my sister, who has a regular cycle and time to ask for a restock, keeps using the entire supply without telling anyone — I told her to start buying her own and it blew up into an argument.

Because my cycle is unpredictable I make a point of buying extras when I can. I assumed my sister — who has regular periods and works full-time — would notice low stock or tell our mum when she had used most of the supply. Instead, multiple times I’ve found the cupboard empty when my period finally arrives. Tonight it’s the middle of the night and there’s literally one pad left in the cupboard and I have no way to get more before morning: I can’t drive, my family will be gone to work, and in our conservative household I can’t ask my dad or brother to buy pads without making an uncomfortable fuss.

"Every time my period comes, the pads are gone because she used them all and never says a word."

I confronted my sister today when I went to the store for eggs and she didn’t mention the pads being low. I told her she should start buying her own pads or at least take responsibility for replacing what she uses. She got defensive and said we share everything and that she’s forgetful. We argued; she felt attacked and I felt tired of always being the one to restock essentials she uses more often. Now I’m stuck wondering if I was unreasonable to expect her to speak up or buy her own.

"She has so much time to tell mum or me to buy more pads, but she never does."

This problem isn’t about money — she earns well and could contribute — it’s about responsibility and basic communication. I feel frustrated because I end up planning around an irregular cycle and she doesn’t even notice the supply is low. I’m now left with one pad and no easy way to get more in the morning, which is stressful and uncomfortable.

🏠 The Aftermath

After the argument, tensions are high at home. My sister insists we share everything and that she’s forgetful; I feel taken advantage of and resentful. Practically, I’m left tonight with one pad and no immediate way to restock tomorrow morning without involving family members in a conversation I’d rather avoid.

For me: annoyance and the logistical stress of being caught without supplies. For my sister: she feels accused and insists she forgets, not that she’s selfish. For the household: an unresolved pattern of unspoken expectations and unequal labor around supplies that needs a clear solution.

Consequences include ongoing friction between us, continued risk of being without pads when I need them, and an urgent need to set a sustainable system so no one is left in a difficult spot.

"I’m tired of being the one who always restocks something she uses constantly without even a heads-up."

Right now it’s mostly resentments and inconvenience — nothing irreversible — but if it continues it will build into a larger trust and fairness issue between us.

💭 Emotional Reflection

This is a common household fairness issue: shared resources require shared responsibility or clear rules. Your frustration is understandable — you’re trying to manage an unpredictable need while your sister, who uses them more, isn’t communicating or contributing equally. That imbalance breeds resentment and occasional emergency situations like the one you’re facing tonight.

Could your sister genuinely be forgetful? Yes. Does that excuse repeatedly leaving you without essential supplies? Not really. Reasonable solutions include setting up a rota, having each person keep one personal pack, or asking your sister to contribute money or buy her own monthly supply. Communication—calm, concrete, and non-accusatory—will help more than shouting in the moment.

People may disagree on tone: some will say you should’ve asked more gently, others will say you had every right to demand fairness. Both points matter — the goal is to fix the pattern, not win the argument.

Here’s how the community might see it:

“She earns and uses them more — she should buy her own or chip in for the household supply.”

“Set a rule: personal pads are personal. Keep one box each in your rooms and a shared emergency stash.”

“Tonight is urgent — ask your mum to grab a box tomorrow morning, but sort out a long-term plan so this never happens again.”

Readers will likely push for practical solutions: clearer expectations, contribution from the sister, and immediate fixes for tonight’s shortage.

🌱 Final Thoughts

You weren’t wrong to call out an unfair pattern — especially when it leaves you uncomfortable and without supplies. Still, the argument shows the need for a practical system: designate personal supplies, split costs, or keep a clear shared emergency stash with agreed restocking rules.

For tonight, try to arrange a quick fix (ask your mum to pick up pads on her next errand if that’s possible). Then have a calm conversation with your sister about a sustainable plan — be specific about what you need from her going forward.

What do you think?
How would you handle the long-term solution: split cost, personal supplies, or a household rota? Share your suggestions below 👇