The Last Crash Of The Sunchaser!: On flashback, Della is hit by a cosmic storm crashing on the moon, and then she is emotionally finding his niece and then she's the mother of Huey, Dewey and Louie, this episode and scene can be very extremely sad and emotional for viewers to see. Everybody gets really angry at Scrooge for his actions, and he enters a seriously severe funk.
Lena's nightmare (The Other Bin Of Scrooge McDuck!) can be frightening for kids, when Magica DeSpell eliminates Webby, turning her into a doll, and makes Webby believe that Lena betrayed her, and destroys Webby completely, waking her up screaming.
Towards the end of "Timephoon!", Louie gets in trouble and he and Della have a heated argument. Della tells him that he took off in a contraption without supervision which was very dangerous, and Louie harshly responded saying "I wonder who I got that from!" causing everybody to gasp shockingly, following Della feeling insulted and punishing his treasure and scheme privileges, and threatening to shut down Louie Inc., causing him to storm off to his room in anger. Della begins to feel very sad for what she did. This may be emotional for viewers to see, since it's Della's first time being mad at a loved one.
Rarely, characters such as ghosts may have a menacing appearance; however, the show goes out of its way to use these characters for comedic value, and as such, these characters should not frighten even the youngest of children.