Would love some advice on a situation with my sister. I have two boys age 9 and 11. I was estranged from my younger sister for many years. I'd kept my distance as she'd had a tendency to lash out in texts or stonewall me. I blocked her eventually. As a result she hadn't seen my boys since they were very small. Over the last few months my mum said she seemed to have changed quite a bit and was more stable emotionally. She has chronic illness - fibro, complex PTSD and ADHD and as a result doesn't work. She has no children of her own. I was still not minded to see her, but accidentally bumped into her in the street a few months ago when visiting my mum and decided "life's too short" and there were lots of tears and we decided to try to patch things up.
Since then things have been fine, and I've met her a few times, but I wasn't ready to re-introduce her to my kids yet. After a few meetings I decided I felt things were going well enough to meet with the kids. We went for a walk, and I couldn't help noticing that she was really intense with my older son, telling him she had missed him and holding his hand and chatting to him while walking ahead, while not giving my younger son very much attention. She was really nice to both when we were all together (when we stopped at a cafe), and she can be very charming and kids love her because she is fun to be around and engaging, But I felt really uneasy about the disparity in the attention and also the intense focus on my older son. She has a lot of time on her hands (due to no work or family), and some of the things she's said make me worried that she is too focused on my kids (especially eldest) and expects too much (e.g. coming on holiday with us!), as she doesn't have very much else in her life at the moment.
My husband is still not willing to see my sister, because he doesn't trust her yet after all the history and feels she needs to prove she can be trusted over time (he knows how much her behaviour has hurt me in the past). If I told him about my unease after yesterday's meeting, he would probably say he didn't want her to see our kids any more at all. I asked both kids how they felt after the meeting and they both said it was really great. But my "mum instinct" noticed that the younger one was in attention-seeking mode, so I think on a subconscious level he was aware that he was being overlooked. He also has issues with being excluded from friendship groups at school and is quite vulnerable (ND) and I'd hate for this family situation to exacerbate that. I want to speak to her about a) the intensity and b) the difference in attention between the two boys, and set some boundaries before we meet again, but not sure how to broach it as she is extremely sensitive, and I'm worried it will put us back to square one.