Could a changeling not know it is a changeling and age as a child?

I was working with my DM today on a character I'm working on. I'd conceived of the PC as a human, but as I was talking over species with him, I blurted out changeling. We both seemed pretty into it, especially as it helped potentially fill in some gaps in my character about his past and his relationship with his parents.

However, I have a question about the nature of changelings. Could one conceivably be unaware they are a changeling for the first 15-20 years of their life if their parents hid it from them to keep their status in society? And would they have 'aged' normally if they'd stayed in that form during that time? Obviously, you could brew some spell to keep this information from the character or some other arcane reasoning, but I was wondering if one was simply brought up as a human in a human society, is there anything inherently that breaks that?

Edit: Thanks for these answers. They've been really insightful and have given me a lot to think about.

Just added context in case it helps at all as I wasn't entirely clear originally: This ignorance was enforced by this character's parents. Since they've reached a high status in society, they don't want their child to inadvertently reveal they are changelings. As they live as one persona, they made their son too, essentially enforcing this identity on him. They claim it's for his own protection once he finds out, but they obviously were acting selfishly and are not great people. The game picks up sometime after the character finds out and he left home due to this rift with his parents.

That all said, I've been ruminating on it, and I'm more open to this character being aware they are a changeling as a child too, but his parents harshly enforcing him to remain as the persona they gave him while he was growing up.