L.G.
Butt in.
Some men seem to avoid confrontation and therefore avoid situations. Now it's been a year and soon it will be two years and the longer he goes without seeing his daughter, the harder it will be to reconnect.
I understand when people are telling you to stay out of it but I'm thinking about the young girl. This will impact her the rest of her life. The rejection and confusion a child must feel when betrayed by a man who should love her most is traumatic. The relationships she will have as an adult woman may be impacted by the lack of her father's presence.
You are a wonderful aunt. Just try to get through to him. If he won't listen to you, try to find a good book specifically written for fathers about the impact of divorce on a child. Go on Amazon.com, look up the topic and read reviews. Maybe he will listen to an "expert".
I am divorced. My daughter's father is the best Dad in the world to her. Thank God b/c we made the best of a bad situation.
I say butt in for your nieces sake. If your brother refuses to listen, then follow the other's advice and be as much a part of this girls life as you can. Filling the void of an absent father will be near impossible but having your love, attention and devotion to this young girl will be something she needs.
Above all...make sure this little girl knows that SHE did nothing wrong. She is NOT the reason her father is not a part of her life. Children blame themselves and wonder what they did wrong to be rejected. Find the words to reassure her that this was his problem, not of her doing.
Keep trying, don't lose sight of her. Good luck.