My daughter (Nalu Fanfic)

Nastu is at Lucy's house again, he snuck in while she was in the shower. Then someone knocks on the door, Lucy starts to turn the shower off and then Natsu yells "I'll get it, Luce". Lucy already knew he was there, so she turned the shower back on. Natsu opens the door to see no one. "Kids and their bad jokes..." Then as he was about to close the door, Natsu heard a short little cry as Natsu looked down his eyes widened he saw a baby...