Conventional thinking has it that if children get "too much" of what they want, they'll become narcissistic adults who only care about themselves.
But this thinking is locked inside the box of the "dominator paradigm," where you "win" by exploiting, excluding, or defeating others. Outside the dominator box is partnership.
In partnership it's understood that we're all connected, so your wins are my wins, and vice versa. Children internalize partnership values when their parents believe that Love is abundant, because such parents tend to nurture generously and unconditionally.
Younger children are naturally narcissistic. When parents model the "healthy selfishness" of partnership and don't resist their children's narcissism, the children will eventually learn that it feels good to care for others.
Today, notice all the ways in which giving makes you feel good, and how others feel good when you allow them to give to you. Let the line between giving and receiving dissolve. That's the magic of partnership!