That sounds like a really important realisation.
I had something similar, which came about as a result of revelations rather like yours from older siblings, and also small comments on childhood memories by my T, which gave me a different perspective to that of the child I was then.

You may have a lot of memories that will look different to you with this added context.

It is a huge thing to have this revelation, and then comes a lot of processing over the next few weeks at least, if not longer. Don't be surprised if you feel emotional at times or if your mood isn't what you expect in some situations. Give yourself time to mull things over in the subconscious, because this is a big change in perspective, and although it can seem straightforward, it takes a while for you to incorporate it.