First Time Aunt

I'm about to be an aunt for the first time. I don't have any desire to be around children or have any of my own. I'm horrified of having to hold a baby or care for one. I'm excited for my sibling and their family, but I'm not excited about a baby being in the family and having to care for a small child. I don't live with my sibling so they'd be visiting maybe 2-3 times a year or so.

I'm just scared and not sure why.