Alijah said:
My friend raises her nieces because their mom (her sister, obviously) has died in a car accident. Was just a general "Happy Day" to everyone, since not everyone who 'raises' a child is actually their 'mom.' :)
In my opinion, being a mother is a state of mind more so than a biological status. You don't need to give birth or even be female to have "motherly" instincts. I guess it all comes down to what you feel responsible for and in what way you do.