Windrider, or Father as we first know him, is a complicated character. Moon Shadow loves his father whole-heartedly and looks up to him. And with Moon Shadow as our narrator, we see Windrider from this admiring perspective.
To be sure, Windrider Lee is an upstanding person. He works hard, finds work and housing for him and his son, is in constant communication with his family back in China, teaches himself English, and keeps up on multiple newspapers. He provides Moon Shadow with all the confidence and love any child could ask for. In some ways, Windrider is kid-like himself, with an active imagination and willingness to believe in something other than the immediate reality.
Windrider's a dreamer who says yes to the supernatural, yes to dreams, and yes to pursuing what he believes to be his destiny. Even when others stand against him, Windrider will follow his conviction. This sense of confidence gets passed on to Moon Shadow, who learns to sit tall and not let racial taunts faze him.
But Windrider's dreamer quality can also be kind of frustrating. Moon Shadow is a super-good sport about it, but Windrider pretty much pursues his own interests and is OK with everything else taking a backseat. Everything including the best interest of his own family. Moon Shadow never outright resents his dad for it, but Windrider could be seen as selfish. After all, Moon Shadow works hard and barely rests in order to support his dad's dream. But what about Moon Shadow's dream, the one of having his family together? Uncle Bright Star points out Windrider's selfishness, but Moon Shadow's faith in his dad won't let us as readers doubt him for long. After Windrider scratches his itch of flying, his dream shifts to be in sync with Moon Shadow's dream of bringing their family together.