Dinah and Dana, voiced by Nancy Cartwright (of The Simpsons fame) and Sandy Fox are characters in the The Land Before Time series. They are infant Triceratops twins, and are main character Cera's niece and nephew. They first appeared in The Land Before Time VI: The Secret of Saurus Rock and have not been seen in the further sequels. They speak in a baby-talk that is unintelligible to Cera, but understood by main character Ducky, and occasionally by their grandfather, Topps.
Dinah and Dana are very rambunctious and adventurous. While Cera was in charge of them in the film The Secret of Saurus Rock, she endured being leaped upon by the twins, having her horns tugged, and being knocked into a mud pool. By that point, Cera yelled at the twins and told them to get lost. They were visibly hurt by her outburst, but when Littlefoot showed up at that moment, telling everyone his theory on Doc being "The Lone Dinosaur" from the legends his grandfather had told them about the night before, and went on to mention Saurus Rock, Dinah and Dana got the idea to follow Cera's order and run away to there.
The twins, being very young and not understanding all of the dangers in the world, are shown to be quite fearless. This is made evident when they boldly leap across a canyon via several rocky pillars (which they had learned to do back at the mud pool, with the bubbles that formed on the top), after only a moment's hesitation. However, they do understand that when Cera or someone else glares at them, they have done something wrong. They were very remorseful when they realized that they had broken off one of the teeth on Saurus Rock after falling from the top of it down, and that Cera and the others were upset by it.
Dinah and Dana are toddlers in the Land Before Time characters' terms, and as such, they are beginning to learn to communicate. Therefore, they speak in a garbled baby talk. Cera does not understand their speech, which furthers her stress over them, but Ducky can easily understand and translate what they say (which she alludes to being a twin herself; thirteen siblings including herself hatched at the same time, even though only six eggs were shown in the nest during her hatching scene in the original The Land Before Time, and any number above two is not technically a twin.) Cera therefore refers to Ducky for help whenever she wants to know what Dinah and Dana are trying to say.
Cera mentions in The Secret of Saurus Rock, while she and the gang are out trying to find the twins, that the first words of one of the twins were "Shiny peep-eye no-no!", although she could not recall whether it was Dinah or Dana who had uttered these lines. Ducky translated the statement to mean "The Bright Circle is shining in my eyes, and it hurts!".
- Although Dinah and Dana do not appear in The Land Before Time IV: Journey through the Mists, it being two sequels before their debut in the series, they appear in a brief cameo in one of the extra section games in the DVD for the movie and playing Hide and Seek.
- In The Land Before Time X: The Great Longneck Migration, Two little Triceratops' that have heads that look like Dinah and Dana's heads are shown playing.
- As revealed, Ducky can understand the Twins' baby-talk fluently as herself being a twin. However it is in turn revealed she doesn't speak well in some translation that the twins say.