- "Shut up."
- ―Jamie Wilkerson, Reese vs. Stevie
The first mention of Jamie's birth was in the episode Grandma Sues, when Lois and Hal first learned the unexpected news that they were pregnant with Jamie. This was not met with happiness. Lois and Hal were already hard pressed financially as it was and it didn't help that Lois's hateful mother, Ida was suing them at the time. When Malcolm and the others learned of Lois pregnancy they were enraged and selfishly voiced how the baby was going to affect them. The boys came to accept it later on.
Jamie was able to communicate to Dewey while in the womb. He told his older brother to do some pretty weird things like paint the kitchen wall green and drive the car among other things. Jamie finally made his first appearance in "Baby Part 2". He was bigger than average, and Lois and Hal initially wanted to induce labor on Dewey's birthday (they forgot it was his birthday ) - much to the chagrin of the latter - but he came earlier than expected. This was mostly due to the stress Lois was in because her mother decided she was moving in with them. There wasn't time to get Lois to the hospital and the paramedics were taking too long to arrive so his eldest brother Francis (who has delivered barn animals before) delivered him and then proceeded to throw up. Reese, Malcolm and Dewey helped in taking care of Jamie after they joined a parenting class.
Like his older brothers, Jamie proves to be a handful for Lois in the episode "Lois Battles Jamie;" refusing to eat his breakfast, getting himself banned from Gymboree and being able to slip away from his chair numerous times. He is also the only Wilkerson child to almost kill Lois by pushing a huge shelf on her, but was unsuccessful, with Lois rolling away just in time. It was revealed that Jamie was acting so crazy because Reese had been giving him three cans of energy drink per day. Jamie was the first of the boys to break Lois' spirit, forcing her to call Francis to get him to remember how she conquered him as a child. Jamie remained silent for the vast majority of his time on the series: the only words he is seen speaking on-screen are "shut up" (to Lois in the episode "Reese vs. Stevie"), although in at least one other episode a voiceover provided his dialogue (e.g. the episode "Blackout", in which he speaks Francis' name).
Jaime's continued survival is nothing short of a miracle. When he was born Lois and Hal's already miserably poor parenting skills had degenerated completely. They rarely seemed to pay attention to him and often left him in the care of a babysitter. A heavy example of this was when Lois and Hal were too focused on a fight between Abe and Craig. He sneaked away and wandered through the air ducts he fell 20 feet and was saved by his brothers by sheer luck. Dewey was a major factor in Jamie's care and survival but also made it clear he'd screw him over in a heartbeat like Reese and Malcolm do to him.
Beginning at the character's first appearance and continuing for some number of episodes afterward, Jamie's gender was left ambiguous. This is later resolved and it is revealed that Jamie is, in fact, a boy, this was proven true in the season 5 episode Vegas where Hal remarked "nice try mister," when Jamie attempted to urinate on him, and when Lois introduced Jamie as her son, proving he is a boy. He was the Wilkerson's youngest child until Lois discovered she was pregnant with a sixth child.
Just like Dewey and Malcolm, it has been shown that Jamie is very clever and manipulative, as he was shown to have outsmarted Reese a few times, tricking him into looking for a candy bar that he pretended to throw, and framing Reese by making Lois think he drew on a wall with a green marker that Jamie gave him.
Jamie has had a few babysitters with the most notable ones being Polly and Clair. Polly was really good with taking care of Jamie and although Clair was really good with Jamie she was extremely annoying to Lois forcing her to fire her, she eventually died at the episode's resolution, which Lois was not expecting. Lois appears to be reminded of the fact that she will eventually die and bakes cookies and asks to go dancing with Hal in order to cope with her mortality and live in the moment. In the episode Morp, Clair had apparently been replaced as Hal mentioned to have dropped Jamie off at his babysitter's house. His new babysitter was never seen or further mentioned so all other information about him or her is completely unknown. In the episode Billboard, Hal mentioned that he hired a one-time babysitter for Jamie, who is never seen or named. He also mentioned that he was turned down by eight other babysitters, when trying to look for one and that Jamie is so notorious for being a terrible baby, that there's a website dedicated to him.
Being so young for the majority of his screen time in the series (only reaching age 3 before the finale), Jamie doesn't have too colorful of a personality. However, there is a bit of depth that gets shed upon his character at some points in the series. Jamie is very precocious and uses his intelligence to do a bunch of sneaky things and cause some trouble. Unlike his brothers, Jamie is pretty clever and manipulative and can avoid getting caught, knowing how to hide guilt and place blame.
Jamie has learned to hate Lois at a very young age and just shares the same opinions for her that his brothers do. In the episode "Reese vs. Stevie", Lois spent days talking on and on to Jamie, trying to get him to talk. Jamie was being driven crazy by her endless yammer, to the point where his first words were "Shut up." Jamie is a lot better at manipulating Lois than his brothers. In "Lois Battles Jamie", Jamie was causing Lois a lot of trouble, being able to drive her to the very brink of tolerance and pushing her to even consider giving up. Lois, however, learned to reign dominance upon Jamie again, realizing that she had the same trouble with Francis, years back.
When Dewey first found out that Lois was pregnant, he screamed a horrible "Noooooo!", knowing that he's no longer going to be "the baby of the family" anymore (Grandma Sues). This was very quickly forgotten on the day he was born, and he and his brothers had to learn how to take care of him (Baby Part 2). Malcolm and Reese abandoned Jamie when they were supposed to be babysitting him one night, and left Dewey to take care of him. Dewey and Jamie bonded together, with Dewey telling Jamie a story about the two of them going on an adventure (Watching The Baby). When Jamie had become 3 years old, Dewey took advantage of Jamie still being in his "learning phase" and taught him to be his servant (Mono). A lot of the ways Dewey treats Jamie is reflective on how he's treated by his family. His aforementioned slave ownership of Jamie is based off of Reese's slave ownership of himself. Not all of Dewey's treatment for Jamie is negative, however. Dewey has been ignored by his family for his entire life and decided that instead of doing the same to Jamie, he should do the opposite and trick Lois and Hal into throwing a party for him, so he could go through life, being noticed (Morp).
Aside Lois, Jamie hates his older brother, Reese, more than lets on. It was revealed in "Lois Battles Jamie" that Reese was responsible in feeding him three cans of super energy sodas. Due to his lack of intelligence and love for violence, Jamie often took advantage of Reese by letting him take the blame for things he has done, such as drawing on walls and other mischief.
Jamie and Hal's relationship is practically unknown, since they rarely interact, but Hal does love Jamie. In "Day Care", Hal convinced Lois to keep the baby, after she admitted to hating him and wanting to get rid of him. Hal reminded Lois that she felt the same way about every previous child they had, assuring her that she'd soon get over it, which she did. At the beginning of that episode changed Jamie's diaper. Jamie peed in the middle of the change and nearly hit Hal with it. Hal dodged it and jokingly wagged his finger and said "Nice try, Mister." as though he was angry.
It's implied from the brief moments in Reese Joins the Army that Jamie likes Francis, like his brothers.In Graduation, he along with Reese and Malcolm burn their troublesome history in the backyard in order to give Jamie a normal childhood they have been denied of.
When Lois was mentally unstable (temporarily) in Reese Joins the Army, Piama was Jamie's primary caregiver. He didn't seem to resist her when he was being fed or put to bed.
- Jamie's gender was kept a secret until the season 5 debut episode, "Vegas" where it was revealed that he was a boy, having peed on Hal and being called "Mister" in the opening scene.
- In seasons 4 and 5, around the time Jamie was first born, he portrayed by twin female babies. In seasons 6 and 7, when he became a toddler with more visible features, he was played by twin male toddlers.
- Jamie's first words were "Shut up." He said this because Lois was trying to teach him how to talk, by trying to put him in a more "verbal environment" by spending all her time with him, talking non-stop about everything in her life. (Reese vs. Stevie)
- Coincidentally, these were also Francis' first words and the first time they were spoken, they were both directed toward Lois. (Flashback)