Technically, they can but you don't have to be related because you can have things in common with another person with are personality traits , and if they have different skin colors it doesn't matter , and you can still have many traits in common , because my sister is darker than me a lot but we still share same traits.
The skeletal system<span> performs vital </span>functions<span>— support, movement, protection, blood cell production, calcium storage and endocrine regulation — that enable us to survive.</span>
