Darla Einstein was born and raised in foster homes, and the amount of time she spent shuffling from one place to another had a permanent impact on how she viewed herself. Regardless of how hard she tried, she couldn't stop herself from worrying that she would always be found lacking in some way.
A drunken Thorne didn't even realize what he was doing at the time, and Darla originally planned to have an abortion, but Thorne convinced her to give the child to him and his wife, Macy (Bobbie Eakes), who was also Darla's best friend. After Macy chose Deacon Sharpe (Sean Kanan) over Thorne, Darla decided to keep the baby and raise it herself. Thorne, knowing he'd lost Macy, decided to lend a hand in raising his child. When the little girl was born, she was named Alexandria in honor of Macy Alexander, who had recently died as a result of an accident. Darla and Thorne had formed a romantic attachment, each realising that they had found the person they had searched their whole life for, and Darla happily accepted when Thorne proposed. The two were soon married.
Unfortunately, it wasn't long before Darla was at odds with Thorne's brother Ridge (Ronn Moss) and his wife Brooke (Katherine Kelly Lang). Ridge wanted Darla to keep her mouth shut about family business and to stay out of things, constantly calling her names such as "dingbat" and "glorified secretary". Darla, however, refused to let Ridge continue to belittle Thorne. While in Thorne's office one day, printing out some photographs of Sally and her together for Sally's birthday, she left the envelope on the desk while talking to Clarke, who was trying to convince her to steal the Ingénue line from Forrester. She didn't see Megan (Maeve Quinlan) take her envelope (containing Sally's birthday photos) off the blotter and put it to the side and put the envelope with the Ingénue shots on the blotter. Darla accidentally gave the envelope to Sally. Ridge was furious, and made it clear she was either one of two things—a manipulator, or a dingbat. Darla ran out of the room in tears and went home to pack her bags, but Thorne stopped her, swearing that no matter what, he would always love her, and did not blame her.
The battle between Thorne and Ridge only got worse until Thorne told his parents that one brother had to leave the company. Both Brooke and Darla campaigned for their significant other in the meantime until Eric and Stephanie made up their minds. They chose to keep Ridge, which prompted Thorne to quit Forrester Creations. Sally saw this as an opportunity and made Thorne a job offer. Thorne accepted and he became president of Spectra Fashions. Darla's continued support and encouragement helped Thorne continue to stand up for himself in front of his family on a personal and business front.
In the fall of 2005, Sally put all her money in Thomas Forrester's designs which were competing against those of the Forresters in a fashion showdown. When Forrester Creations came out on top, Sally was devastated and knew that her company would soon face trouble. Shortly after, Sally gathered Darla, Clarke, Thorne, Thomas and her faithful Spectra employees at her office to announce she was going to shut down the company and as a retirement gift to herself, take a long cruise around the world. This of course was a ruse on Sally's part as she was really retiring due to health complications as she was now a wheelchair user. When Darla realised what was really going on with Sally, she invited Sally to come and live with her and Thorne at their beach house as Sally was like family to her.
Darla again saw little air time until mid-2006. One night, after Alexandria's fourth birthday party, Darla's niece Phoebe (MacKenzie Mauzy) got a flat tire and was stranded at the side of a busy road. She called her mother Taylor (Hunter Tylo), but the call was interrupted when a mysterious bearded man approached Phoebe and she screamed and dropped the phone. Worried about her daughter, a frantic Taylor, who had been drinking, got into her car and rushed to find Phoebe. Phoebe had gotten back into the car and, unbeknownst to Taylor, also called Darla. Darla came to Phoebe's rescue, and as she was changing the tire, a speeding Taylor, who couldn't see through the fog, hit Darla with her car. A horrified Taylor tried to revive her good friend and former sister-in-law, and Phoebe called an ambulance. Darla was rushed to hospital in critical condition. A devastated Thorne and Sally gathered at Darla's bed as she flatlined and died with Thorne at her side.
Darla occasionally appears to Aly in a cloud-like circle, and the two carry on conversations. Only Aly can see her, but she has the power to make her presence known to others, in subtle ways.
During a feature on what storylines were working and not working for the show, a Soap World reporter thought Darla's return to help out Aly was "a disaster". The reporter wondered why the producers brought back a popular character if they were not going to use all of her, saying "forcing a fun and effervescent actress like Schae Harrison to play a 'dismembered floating head' is stupid."