Jenna has trouble taking care of Elena and Jeremy. She had a friendship with Elena while she had to be the scolding parent to Jeremy. Jenna approved of Elena's relationship with Stefan. Elena also supported Jenna when she broke up with Logan and when she began dating Alaric. Jenna later reveals to Elena that Logan had returned. Jenna begins to worry when Elena doesn't come home and yells at her. However, Elena asks Jenna if she's adopted and gets mad at her for not telling her. Jenna helps her search for her birth mother, Isobel, and tells her all that she knows about her. Elena gives Jenna vervain perfume to protect her. Jenna later tells Elena that Alaric's wife was called Isobel and she died. Jenna gives Elena Trudie's address.
Jenna helps Elena get ready for Miss Mystic Falls by doing her hair. They talk about her mother and Jenna tells Elena she's proud of her. Jenna witnesses Elena dancing with Damon and asks Alaric why she's not dancing with Stefan, but he doesn't know. Jenna helped Elena get into her corset for the Founder's Day Parade. That night, Katherine returned to town and posed as Elena to Damon who kissed her. Jenna interrupted their kiss and was outraged that Elena was cheating on Stefan.
Jenna and Elena meet again at the hospital and Elena's confused when Jenna says she told her where she was going. Damon then realises that Katherine is back. Jenna doesn't like seeing Elena talking to Damon. Elena later attends Jenna's barbeque with Caroline.
Katherine compelled Jenna to stab herself to get back at Elena. Fearing for everyone's safety around her, Elena broke up with Stefan. Elena, Matt, and Alaric helped her recover. Elena later discovers that Jenna has invited Elijah inside. When Isobel returned, Jenna was heartbroken that Elena had known she wasn't dead but hadn't told her. Jenna refused to listen to Elena and Alaric and left town temporarily.
While talking to Elijah, Elena received a call from Stefan, telling her that Jenna was back and knew about vampires. She arrived at the house to talk to Jenna and revealed it was all true. Jenna was scared of her, but let her hug her for comfort. Jenna later received a call from Elena, but it was really Katherine. Jenna left the house to find Elena but was captured by Klaus. Greta lead Elena to where Jenna's body was and revealed she was on the way to becoming a vampire. Elena begged Jenna not to drink Greta's blood, but she did so, completing her transition. Jenna apologised to Elena for failing her, but Elena said that she had failed her instead. Elena tried to convince Klaus to release Jenna and then refused to choose between Jenna and Stefan. Jenna comforted Elena and attacked Greta, but Klaus killed her, horrifying Elena, who cried until Klaus killed her, too.
Elena later attended Jenna and John's funeral, crying, and laid a rose on Jenna's grave.