As an atheist, I feel the core principle of me is to have a open mind, to not push a belief on another, and let them make their own mind up. The only thing to offer, be it a friend or family, is a different perspective when appliable.
I am a fan of personal spirituality and if someone adopts a religion while seeking out their spiritual path, so be it.
I think there is a higher chance a atheist parent (proper atheist, not some cynical mad at god nonsense stuff) is more likely to have a open minded
and more science oriented kid though as they teach to think and question verses the opposite.