If you are an older sibling or the oldest do you f

So I am the oldest on my birth mom’s side. I have a youngest sister who is 7 (younger than my 8 year old) as I have other siblings as well. But anyway ever since she born even before I felt like I needed to “take care” of her in a since. I mean my mom is 8 hrs away from me. But before she was born I was the first person to buy baby things, when she needs stuff I’m sending it. Idk 🤷🏽‍♀️…