Let me start with some background. I (17f) am the youngest of five. My older siblings are Hannah (19f), Jace (22m), Jayden (24m) and Aurora (26f) and Aurora was the first to have a baby almost a year ago.

I have a really good relationship with most of my siblings and Aurora is the exception. She always disliked me. I don't know why. It's not because she's no longer the only girl because Hannah's also a girl. It's not just because she didn't want younger siblings because I was the last to be born. I never shared a room with her so it's not that. We have the biggest age gap but it's not like some crazy big 15 or 20 year age gap and it's not like there's a huge age gap between me and Hannah either. My siblings have their own theories about why she's like this with me only. From seeing an extra girl beyond Hannah as competition to resenting the fact I made us an odd number group of siblings and her being weird about it. Jayden believes some of it is because Aurora thought our family would get a puppy and instead mom announced she was expecting me. He told me he remembers how excited she was and how upset and disappointed she got when she found out how our family was going. He remembers her never being excited and he said he remembers her being excited about Hannah and wanting a sister when mom was pregnant with Hannah.

But none of us know for sure. She never said why. It drove our parents crazy when we were younger. She would intentionally exclude me from stuff and she'd come up with things for her and the rest of our siblings to do together and she'd try to leave me out. She'd throw tantrums when she wasn't allowed to leave me out. She'd do nice things for our other siblings but never for me. It was petty stuff too. Like one day we were all sitting down to do homework and she got herself and the others a glass of water but she didn't get one for me. Another time it was she brought candy home from the store and shared with our other siblings but not me. She got in trouble for that kind of thing.

Our parents had her in therapy and they had some pretty strict rules about being mean and intentionally excluding others in the house like that. Nothing made a difference because even if she didn't do that stuff she was still hostile around me but not the others.

It made some of us question if we were all full siblings and our parents even went as far as doing a DNA test with all of us to prove we were. I think they mostly did it to reassure me because that stuff did make me second guess everything.

When Aurora moved out after high school and went to college she never called or made an effort to have a relationship with me then. She'd call and text our siblings. She'd do stuff with them when she had time or if she wanted to visit. But you'd think I didn't exist with the way she ignores me. It got no better when she got married either.

The whole thing has made her less close to our other siblings. Hannah, Jace and Jayden don't like the way Aurora treats me and they have spoken up so many times. Aurora hates that and it made her more bitter toward me.

Taking it to now. She has a daughter who's almost 1. I never met her daughter. She has refused to let me meet or interact with her child and has argued with our family over it. She said she didn't want me to be her kids aunt and so she's keeping us from forming a relationship. But now she wants a babysitter and she knows I'm planning to go to college for childcare related stuff. So she asked to have me babysit every second Friday. There was a whole talk about it and she went to our parents and not to me so she's still being distant. Our parents thought it was a great idea because it might soften her to see me do a good job with her child.

But I don't want to and said no and I did that for so many reasons. I worry she'll let me get attached and then stop all contact between us. I worry she'll teach her daughter to hate me and if she has more kids and they get included in the deal it'll be me against kids who were taught from birth how to hate me. And I worry she might be extra hard and any bump or bruise her kid ever gets she'd blame on me and maybe she'd even call the cops or CPS on me. Maybe that all sounds paranoid but it's the way I think about this stuff.

My siblings understand and they think I'm right to say no. My parents are pushing for me to say yes and Aurora is in the background insulting me for it too. My parents said this might be my only chance to get to know my niece and any future nieces and nephew's from Aurora and they told me not to like childish issues get in the way of that. They said I always wanted Aurora to give me a chance and now she is. So I should embrace this chance and do all I can to win her over and show her what she's missing out on or at the very least establish a connection with her child.

I should probably mention Aurora is saying I'll be paid the normal amount for a teen babysitter.

AITA?