Tria, originally voiced by Camryn Manheim, and later by Jessica Gee, is a character in the Land Before Time films and TV series. She is a Triceratops, which is known as a "Threehorn" to the characters in the series. She is the stepmother of main character Cera, the new mate of Topps, and the biological mother of Tricia. She is kind, loving and brave, though can also have a tendency to be timid. Tria is far more lively than her mate, but is also far more hedonistic, enjoying relaxing in warm mud and collecting shiny gems. It is revealed in her first appearance, in The Land Before Time XI: Invasion of the Tinysauruses, that she and Topps, Cera's father, first met when they were much younger. As very little else on the matter has been mentioned, it is uncertain why they went separate ways, but in the eleventh film, they reunite when she moves into the Great Valley. This displeases Cera, who is used to being the center of her father's attention and does not wish to share it. Tria, however, tries to show Cera love and care, and is hurt by her coldness. When she finally confronts Cera on the matter, the latter begins to feel guilty, and accepts Tria's proposal of becoming "Someone who will help your father "worry" about you."
In the meantime, Topps wants to show Tria his love by letting her have the first treesweet off of a special treesweet tree, from which everyone in the valley gathers around once a year to enjoy the sweet flowers which bloom from it. However, when Littlefoot accidentally knocks all of the flowers off of the tree, and blames it on a herd of Tinysauruses who devour all of the blossoms, Topps vows to make sure they are all exterminated. Tria at first believes what he is doing is for the best, until she catches her first glimpse of the little longnecks. She immediately finds them to be adorable, and thus tries to stop Topps from chasing them down. When he tells her off for it, she temporarily separates from him, until Cera rationalizes her father's behaviour. Tria and Topps then reconcile.
In The Humanization Series, Tria Runs A Beauty Salon, A Jewelry Store, Been Known As A Singer, And Known To Have A TV Show Like Oprah Winfrey.