I've been with my SO for almost 3 years, and he has a 4.5 year old daughter with his ex. His daughter has always really liked me, and as far as my SO is concerned, I'm great with kids. ...But being around his daughter has singlehandedly turned me childfree. I feel like I'm watching a train wreck in slow motion. It's a combination of the way his kid acts and the way he and his ex choose to parent her. The daughter is...unlike any child I've ever met. She is INSANELY ADHD/ADD--she loves to run around and yell, and nothing but Netflix can capture her attention for more than two minutes at a time. She is incredibly bossy, and gets frustrated when people aren't following her commands. She is wholly incapable of entertaining herself (other than with Netflix)--she needs your attention at all times. She's also the least intellectually curious kid I've ever met. Every time we've taken her to a kid's museum, her behavior is so different from every other child there. While all the other kids (even ones younger than her) are capable of entertaining themselves with the different exhibits, nothing really interests her past her ability to touch it for a few seconds before moving on. I'm pretty sure her verbal skills are slightly delayed, and as best as I can tell she'll probably need to be in special ed once she's in elementary school. She's also not naturally very sensitive to others' emotions, though she's become fairly adept at manipulating her parents.

Having said all this, she isn't my kid, and we get along really well, so why do I even care? Well, idk, I can't help but feel sorry for how she's going to turn out (and, from a more selfish perspective, I'm terrified of what I'm going to have to deal with in a few years). My SO sees her as "gifted" and rarely disciplines her. She has a tendency to only want to hang out with children much older than her (like 8+ years old), and my SO has explained it away as "oh, it's because she's so much more advanced than children her own age, so she can't relate to her peers." Meanwhile, the BM is literally incapable of disciplining her (apparently whenever the kid starts crying, the BM IMMEDIATELY caves), so my SO feels less of an incentive to discipline her, since then he's the "bad parent." My SO has also admitted to me that his daughter doesn't respect her mother (...at the age of 4...) because the BM cannot set boundaries. Neither parent has ever put her on any kind of consistent schedule either, and she switches off between them daily, which I don't think helps.

I can't say anything to my SO about how to parent his kid, so I tend to just avoid outings with her. But I can tell that my SO gets upset when I don't want to go out with them, especially since his daughter likes me so much. I always treat her warmly, but gah, I know in a few years she's going to become a really unbearable preteen thanks to her parents.