This article or section contains spoilers for 2018 novel Serpentine.
Proceed with caution.
Peter Parnell is Donna's son, and Ted Forrester's future step-son. He also has a younger sister, Becca, of whom he is very protective. He is close to six feet tall. He has a black belt in judo and is working towards a black belt in another discipline.
When he was eight Peter watched his father being murdered by a werewolf. While his mother cowered, he took the silver-loaded gun and killed the werewolf. He then maintained the adult male role in his family after that, until 'Ted' entered the picture. He was suspicious of Ted in the beginning.
Peter and his sister are kidnapped by Riker in Obsidian Butterfly and he is raped. Anita saved him, while Edward saved Becca. After the ordeal he takes up martial arts and later becomes Edward's apprentice.
Unlike his family he is aware of Ted's true identity and accompanies Edward when he comes to Anita's help in The Harlequin. He is mauled by a weretiger while trying to save Anita’s life. After being hospitalized the doctors offer him a new ‘after attack vaccine’ that would cancel out the lycanthropy if he had caught it, but if he hasn't he’d get the strain in the vaccine, a weretiger. He decides against the vaccine.
In Hit List it is mentioned that he talks to Anita on the phone once or twice a month to discuss his training. He is scheduled to go on his first hunt with Edward in fall of the year he turns eighteen. Anita agrees to accompany them on the hunt.
Edward believes that Peter might have a crush on Anita, because she was the first woman he saw after having his first sexual encounter. He has also been dumped by his first two girlfriends for being too rough.
By the time of Serpentine Peter has grown into a big, ruggedly handsome college-age man of nineteen, although he's self-conscious about the scars he got from the weretiger in The Harlequin and still carries a lot of rage within him. The situation is made more complex when a friend of Donna's, Dixie, is having problems in her marriage, has a crush on Peter, and is simultaneously emotionally manipulated by Terry Rankin. Dixie keeps trying to tell Becca that her dad is a cheating waste of space, and when Peter has to stop Dixie physically and carry her away she bites and scratches whatever she can reach. He doesn't know how to set her down without hurting her or allowing her to hurt him more, so he brings her to Anita's group for help.
Peter then gets into an argument with Donna about her relationship issues and confiding in Dixie, until Edward arrives to the mess and their upcoming marriage is almost over before the wedding. They all hug it out in the end until the drama with Dixie distracts them anew, and they finally realize she has also stabbed Peter into a thigh with a fountain pen. He doesn't realize it's a big deal, but a piece of the pen has broken off into the wound and has nicked his artery. Edward starts first aid, but the wound starts bleeding a lot and Peter passes out from the blood loss before the ambulance gets there.
Edward drives with Peter in the ambulance to the hospital, while Anita stays behind for Becca. Consequently Anita has to deal with the detectives who try to place the blame of the incident on Peter and also suspect him on the disappearance of a young woman who is also a guest at the hotel. The doctors get Peter's bleeding stopped at a surgery, but he is healing faster than a human normally would, which is apparently a common side-effect of the vaccine they give out against lycanthrope attacks. Only Peter didn't take the vaccine, and Anita speculates that Cisco bleeding out on top of Peter during the incident worked as a makeshift vaccine. It also turns out that Peter wasn't fast enough to remove Dixie from Becca's vicinity and she heard the accusations anyway, but doesn't believe a word of them.
Donna wants to postpone the wedding at the beach since Peter can't attend in his state, but Peter is having none of it, and then they learn that another friend of Donna's, Denny, has also gone missing. Donna stays at the hospital with Peter while Edward goes to save the day, and in the end the wedding is postponed only enough that both Denny and Peter recover well enough to be able to attend the ceremony at the beach. Peter tests inconclusive for lycanthropy, which doesn't get him listed as having a contagious disease yet but may or may not affect any plans of joining armed forces. It makes him more determined to join Edward's business instead. Anita is still hoping that won't happen. If he does, they plan on taking him for his first hunt at twenty-one.
Peter's age is inconsistent in the series. In Obsidian Butterfly, he is 14 years old. The Harlequin takes place seven months later, but he's aged to 16 by then, which is not possible. This is related to a larger timeline inconsistency related to the time that's passed between Obsidian Butterfly and The Harlequin; see the inconsistencies section of the Timeline article for more details.
In Hit List, which takes just under two years after The Harlequin, he is 17, which could work with either his age from Obsidian Butterfly or The Harlequin. It's additionally stated that he'll be eighteen by fall the next year, indicating that he is only recently 17 and will turn 18 next year. In this case, Peter would have turned 16 the year prior, and he should have been 15 in The Harlequin which would make his age consistent with Obsidian Butterfly. This is possibly an attempt to correct the inconsistency with his age in The Harlequin. This would also place his birthday sometime between May and August.
In Affliction, which is nearly exactly three years after The Harlequin, Peter is 18. This is consistent with Obsidian Butterfly and Hit List, leaving his age in The Harlequin as the only inconsistency.
In Crimson Death, Peter is 19, which could work with either his age from Obsidian Butterfly or The Harlequin. If The Harlequin remains the only inconsistency regarding his age, then this would place his birthday sometime between May and July.