Insider trader (got hold of other bids and so made sure Steve Andropolous's was the lowest) 
During her pregnancy, faked an episode of preeclampsia [May 1984]
Diana McColl was the spoiled daughter of Craig Montgomery's boss, Whit McColl. A wealthy man, Whit was newly married to Lisa Miller Colman, who first thought that Diana was some floozy who was trying to get her digs into Whit and break up her marriage, until Whit properly introduced them. While setting into her family life, Diana caught Craig's attention. Though left impotent from an explosion, Craig took one look at the vivacious Diana and realized that his potency was returning. While engaged in an affair with Craig, Diana found that her heart belonged to his nemesis, Steve Andropolous, who was in love with Craig's wife, Betsy. Though Diana tried to work her wiles on Steve, he snubbed her and she retaliated by telling Craig that Steve had borrowed money from her so he could fly to Spain to be with Betsy. In the meantime, Diana and Craig formed a partnership and converted the Stenbeck yacht (which Whit had bought for Diana) into a nightclub. At this time, Craig, wanting Steve away from Betsy, set him up to be blamed for the theft of Whit's rare coins. Not knowing of Craig's involvement, only knowing that Steve was in trouble, Diana hid Steve and later helped him to evade the police and a gangster named Vermeil who wanted to stolen coins. While Steve was on the run, Diana learned that Craig was embezzling from their club! Though Craig pleaded poverty, Diana was unsympathetic and told him she wouldn't call the police if he sold his half of the nightclub to her. With no choice, Craig was forced to comply with her demand.
Not long after, Steve was cleared of the charges and Diana decided to further help Steve by helping him to set up his own construction company and making sure he got his first contract, by getting a hold of all the bids and making sure that Steve's was the lowest. However, he couldn't unite with Betsy because she decided to stay with Craig, after Craig became paralyzed after a fall. Distraught over losing Betsy, Steve finally turned to Diana for comfort. However,, Diana had a sneaking suspicion that Craig was faking and tested her theory by throwing coffee on his lap!
As Diane suspected, Craig jumped up and gave himself away. Diana was willing to keep quiet since she wanted Steve and Betsy apart also. However, when Craig went as far as to kidnap Betsy's young daughter, Danni, a guilty Diana told Steve the truth about Craig. Just as she thought she'd lost Steve, Diana learned she was pregnant! Telling Steve, in the hopes that he'd marry her, she was saddened when he didn't make the offer, since he loved Betsy. Alone and pregnant, Diana accepted an offer of marriage from Steve's good-guy cousin, Frank, in order to give the child a name. The only problem was that Diana still yearned for Steve. Feeling trapped, she feigned an episode of preeclampsia in order to get his sympathy. Unfortunately, a drunk Whit showed up at Memorial and demanded to know why Frank was cavorting with Maggie Crawford if he was the father of Diana’s baby! Things went from bad to worse when Steve (who was in actuality the father) tried to help Diana and he found himself at the receiving end of Whit's tirade. Distraught at her father's anger, Diana ended up losing the baby, for which Steve blamed Whit.
Not long after, Whit was murdered and, in his will, he stated that Diana (who he believed was acting like a tramp) would only get her inheritance if she married and had a legitimate child. Diana saw her chance with Cal Randolph, the father of an abandoned child, Jill, who Maggie was planning to adopt. Getting on his good side, Diana convinced Cal that they could marry so he could get custody of Jill. However, her plan was fooled when Cal decided that Jill would be better off with Maggie than him and refused Diana's offer. Diana's future then took a turn for the worse when her older brother, Brian, was forced to liquidate the family's assets, which included her yacht club. Though her family offered to help her, Diana made the decision to stand on her own two feet. Very soon after, Brian rewarded her newfound maturity by buying back the club for her. In a moment of kindness, Diana decided to allow Cal to manage her club. Unfortunately, that was a huge mistake. Cal bought liquor without paying taxes and was threatened with jail time. To avoid jail, he offered to use Diana's club for a sting operation to expose a gambling syndicate run by a man named Haskell. Unfortunately, the operation was less than successful, and when Haskell started threatening her family, a frightened Diana fled and disappeared in the witness protection program.