"girl1:"saw daddyniall in 'this is us'  girl2:" have you read his fan fics?" girl1: "not yet
refers to a nickname for niall horan on tumblr there is also a fan fic called daddy! niall and i believe a url daddyniall
""girl1:"saw daddyniall in 'this is us'  girl2:" have you read his fan fics?" girl1: "not yet" What is the definition of "daddyniall"?