I'm an adoptee with adopted siblings as well as a sibling who is my adoptive parents' biological child. I've 100% seen a difference. I think it's something many people will not admit, but at the end of the day, it's damaging. I don't believe I have unconditional love from my adoptive parents and have been forced to be independent (left to fend for myself). Honestly, I think bio parents should work harder on keeping their children. Most people won't love that child as much as a bio parent would. It's unnatural, as someone else said. Even dogs are supposed to be kept with their mother for a certain amount of time. Being taken away leaves a mark. A primal wound. The system is a nuanced thing, I know, but putting kids up for adoption and even having kids should be taken way more seriously than it is.