Only Child Syndrome

Narcissa smiled and wiped her tears away with her thumbs. "Goodness you're so grown up. I always worried that you'd be a terrible sibling," she laughed and leaned into his embrace. "You've always been so spoilt but," she met his eyes. "You're going to be a wonderful big brother... A wonderful father." (Oneshot. Dramione. Theo/Harry/Narcissa Triad)