How much would you really learn about yourself from meeting a close relation that you've never known? (see details).

I was listening to something on the radio this morning about someone who was about to meet siblings they never knew they had, and were excited because they didn’t know who they were and felt that this was going to tell them. (I have a similar feeling relating to my deceased father.)

But how much do you think a close relation such as a sibling or a parent that haven’t actually featured in your life (for whatever reason) really impact on who you are?

If the chance to meet those people came up, do you think you would end up realising that the person you are is more formed from the people you actually grew up around?