AITA for saying she’s too young for a debit card when she’s clearly not

My (42f) mother has a 17 year old daughter (F17) and a 19 year old son (M19). Her daughter has a 5 month old baby boy. My mother has always said that age restrictions are important when it comes to finances, so when my sister was born, I was 13 and had my own job, and my mother trusted me enough to give me control of the family finances. <br><br>This has caused problems for a while now, as my mother still works full-time, and my sister has become incredibly reliant on me financially. I have money of my own, but I’m also married and we have our own expenses to keep in mind. My sister has no job, and has been borrowing money from me and my husband to pay her bills. We’ve told her several times that she needs to find a job, but my mother steps in and covers her expenses. <br><br>However, I just had my second child and my mother has given me full control of the household finances again, like she did with me. This has caused problems for me, as my husband and I are sharing money to pay the bills. We have agreed to split everything 50/50, but I have been receiving money from my mother for food and clothes, and some other things. My husband has also been buying me treats with our shared money, but I feel that I shouldn’t be receiving money from my mother for everyday expenses, like groceries. <br><br>I talked to my mother about this, but she said that I was too young to manage the money, but then she also said that her daughter is too young to have a debit card. <br><br>My sister was upset about this, as she’s recently applied for a job but hasn’t been accepted yet. She currently lives with my mother and pays no rent. Her baby’s father pays child support, but my sister uses most of it to buy luxuries. <br><br>I told her that my mother was right, she’s too young to have a debit card. I know that I am too young to be in charge of the finances, especially now that we’ve had a discussion about it. <br><br>AITA?