Childhood abuse and PTSD dreams?

So when I was a child, I was abused by my older brother who was about 14 or so years older than me (yes, my parents had us far apart. I have another brother who's older than me but younger than the one that abused me.) He abused me physically and emotionally, and possibly sexually. I say possibly because I'm not sure. He never touched me in a sexual way or made suggestive remarks towards me, but he did make fun of and tease me about my developing body once I hit puberty, mainly about my breasts. I also recall him spanking me once or twice when I was a kid as punishment, and even though he didn't intend it in a sexual way and I was too young to know what sex was, it still felt violating and humiliating. I remember the violation and humiliation more than I remember the pain.

That's not the point though. The point is, I've been seeing a therapist about this for years and dealing with it, but only relatively recently I've begun having bad dreams about my brother. I'm not sure if you could call them PTSD dreams or not, I've never been formally diagnosed with PTSD. These dreams also aren't flashbacks of the things he did to me, but new scenarios created from the memories of what he did to me, I guess, as well as my fears and concerns regarding him. These dreams, I think, only really started or became more common after my nephew was born about a year ago. My brother and his wife had a baby, and I admit I've been worried about him abusing his son. For now it seems like he's turned over a new leaf, he hasn't hurt me in a long time and he seems to be nicer now and friendlier towards me. I haven't seen any overt abusive behavior from him towards his child, but still I can't help but worry. I don't know if my sister-in-law knows about what he used to do to me. Either way, I plan on protecting the child and keeping a close eye on him. If my brother tries anything funny, I swear I will protect my nephew and be the first to call the police on him. I won't let him do to my dear nephew what he did to me. Still, these dreams, why am I having them now? You'd think if I were going to have PTSD dreams I'd have had them years ago, not now. If these even are PTSD dreams, idk.

I also don't know if it makes a difference but of the dreams I've had since my nephew's birth I've had about three, I think, regarding my brother and my worries. In the first I was hiding from my brother, like I used to when I was little and he was on one of his rampages, but I was an adult as I am now and holding my nephew, protecting him. In the second my brother became famous, or was going to anyway, and I worried that nobody would listen to me if I were to tell them about how he abused me. I was afraid others may not believe me or may trivialize my abuse, saying that what he did was just one little bad thing compared to this other great thing he did to become famous. The third, and most recent, was one in which it was just me and my brother and he got angry and tried to/did spank me for misbehaving. What does it mean? Is this a good or bad thing, that I'm having these dreams? And are they actual PTSD dreams, or something else? Do I have PTSD? Sorry for the long post, and thanks so much to anyone who responds to it!

I'm going to give you my 2 cents very quickly, based on my still limited understanding of C-PTSD (so not PTSD, that I'm not familiar with).

C-PTSD dreams, imo, are very dark dreams, sometimes incomprehensible. You may wake up very scared. They're incomprehensible and very symbolic because they come straight from the unconscious. You may still feel very distraught a long time after you wake up.

Your dreams seem different, they sound more like regular nightmares, more literal, the kind I experience now that I'm in touch with my feelings, the kind that express quasi-conscious fears.

Hope this helps a little - I can't tell whether you're suffering from PTSD or not though, this is not something I'm able to determine here.