Dad should first consider the age of the kid. For very young kids, he should avoid really terrifying details. He can also give the kid a sense of security during the story, like saying 'but this can't happen in our house' or 'I will always protect you from such things'.
He should give the story a happy ending. This way, the kid will not be left with a feeling of dread. For example, if the story is about a haunted house, at the end, the family in the story can make the house a friendly place by being kind to the ghosts.
Once upon a time, Dad and Ada went into an old, abandoned house. The moment they stepped in, the door slammed shut behind them. They heard strange whispers all around. Dad held Ada's hand tightly. As they walked further, they saw a shadowy figure at the end of the hallway. Ada screamed, but Dad tried to be brave. They quickly turned around to find another way out, only to discover that the rooms seemed to be changing and twisting around them. It was a nightmare they couldn't escape.
Perhaps Tommy's dad, Stu, could tell a 'Rugrats scary story'. He might be reminiscing about something that happened when he was a kid and it just comes out as a bit of a spooky tale. Or it could be one of the babysitters who decides to tell a story to keep the Rugrats entertained, not realizing how scared they might get.
I don't know the specific story Bart tells. It could be about a haunted house with creaking floors and strange shadows, or a spooky forest filled with eerie noises and unseen creatures.
Sure. There was a kid who moved into an old house. Every night, he heard strange scratching noises coming from the attic. One night, he couldn't take it anymore and went to investigate. When he opened the attic door, a cold wind blew out. He saw a pair of glowing eyes in the darkness. Terrified, he ran back to his room and hid under the covers. He never went back to the attic again.