Jo tries to help a married couple in Illinois with five children, including an openly defiant teen and a 4-year-old with separation anxiety.

Parents Keith and Sonya are so overwhelmed with their three older boys, Jett, 5 Gage, 3 and Trey, 2, that they're missing baby Myles' cues about wet diapers, feedings, etc. Mom literally has to run through the house after the active older boys with Myles hanging off her arm, head bobbing dangerously. Keith is a flight attendant and travels frequently, and Mom doesn't have enough arms for all the work! Neither parent is consistent about discipline, and their go-to punishment is "saucing" the three older kids, putting a dab of hot sauce on their lips.

Jenny and Tony Swift in Sacramento, California, have five lively and unruly children, ranging in age from 11 years old down to a baby of 9 months. Jenny, a stay-at-home-mom, enlists several other authority figures to raise her kids, including a young nanny. The four boys play around the unfenced, unalarmed swimming pool, riding bikes near the edge and not even wearing helmets. They openly defy Kadie, jumping from bedroom dresser to bed. In addition, Jenny's mom, Gloria, pops in regularly to help out with the kids and is the only person who has instituted any kind of discipline that the kids respond to.

Traveling to a secluded island off Seattle, Jo meets Rikki and Jenye Young, who forego discipline in a misguided attempt to compensate for uprooting their three young sons so often. After four moves just this year due to Rikki's sales work, Nicco, 6, Makai, 4, and Crew, 21 months, are out of control -- and Rikki and Jenye are at their wits' end. The boys run wild in and out of the house, and sometimes their safety seems in jeopardy. Rikki can't sleep because little Crew consistently wants in his parents' bed. And when Dad occasionally tries to inject some discipline into the boys' lives, the result is explosive tantrums. To make matters worse, Mom's first instinct is to comfort her children, not to stand firm with her husband. With a fifth move looming, Rikki and Jenye increasingly worry about the long-term effects of the family frenzy on their sons' lives.

A little dictator named Dylan rules the roost in the Van Ackers' Oak View, California, home, and parents Jessica, 34, and Kevin, 35, need to be liberated from his relentless tantrums and disrepect. Now three years old, Dylan refuses to be potty-trained and, worse, he's become anemic from his unbending preference for sugary snacks over vegetables and other nutritious foods. Supernanny Jo Frost embarks on a family revolution to instill parental discipline for the benefit of all, including six-year-old Emma, who can't even have quiet homework time with Mom without the distractions of her little brother's constant crying and complaining.

A trip to Kissimmee, Florida, is no vacation for Supernanny Jo Frost as she finds the Fernandez family falling apart. Former high school sweethearts Jerald and Marla married young and now, years later, their relationship is in trouble. That's largely due to their inability to control their defiant 12-year-old daughter, Desiree, and two overly aggressive sons, Elias, 5, and Eulisis, 3. Mom's completely exhausted from trying to do it all, while Dad's frustrated and often unwilling to step up to the plate. Meanwhile, Desiree's developing a bad attitude and her grades are plummeting. And Elias and Eulisis are learning the wrong lessons -- that kicking, screaming and crying pay off to get what they want.

Stay-at-home mom Joey-Lynn and her husband, Glenn, have five spirited daughters and a granddaughter all living under the same roof, and the exhausted couple have abdicated discipline. Their oldest, Samantha, 20, had a child as a teenager -- their granddaughter Krissy, now age 2. Joey-Lynn and Glenn had Samantha when they were teenagers themselves, and feel as if they have failed as parents since Samantha had a promising future that has been changed by her young motherhood. Samantha and her next-oldest sister, Brooke, 17, despise each other and curse at each other in front of the younger siblings -- Savannah, 10, Hailey, 6, and Haidyn, 1+1/2 -- who in turn act out with boundary-pushing and aggressive behavior. Mom defers all discipline to Dad, who simply yells and doesn't follow through.

Traveling to Phoenix, Arizona, Jo Frost must help this family on the brink: Meshell can't say "No" and overindulges her children to make up for the extras she never had; David tries to instill some structure and respect, but he's exhausted from long days at work and too often shows his temper; without clear boundaries and consequences, the kids are mostly out of control - whether it's the youngest, Avarie (3), refusing to give up her bottle, or siblings Ainsley (5), Landon (7), Meryn (10) and Kendall (12) back-talking, fighting or leaving their clothes in a heap. The oldest Kesley (13) is increasingly troubled by her parents' mixed signals. She's considered responsible enough to babysit her younger sisters and brother overnight, but isn't allowed to go to an afternoon movie with her friends.

Stay-at-home mom Danielle, 33, is overwhelmed by her misbehaving two boys, Carlo, 4, and J.J., 3, while still trying to do her best with one-year-old Julia. While husband Joe works long hours, Danielle has to deal with J.J., who hits, kicks, slaps and pinches, and with Carlo, who is a picky eater and has a scream that, as his mom says, "takes your breath away." Ironically Danielle was a parenting educator before having children, but she doesn't enforce her own house rules and has lost sight of her personal dreams in the chaos at home.

"This is my life, and it sucks," admits father-of-four Chris Potter. Chris and his wife, Joy, have four children who they feel are very disrespectful. Joy says that Chris is too "old school" -- yelling, scaring the kids, and being too strict and temperamental. Noah, 10, has a strained relationship with his father, who berates him as a brat when he's angry, and the younger siblings also come under fire. Chris feels that Joy is undermining him by challenging his parenting style, which his own mother didn't do with his dad when he was growing up.

While Marine Major Chris Merrill is stationed overseas for a year in Afghanistan, Mom Beckie, 33, is fighting another battle on the home front with their four young children. Garrett , 4 and Elena, 4, are cousins they adopted from Guatemala; Eddie, 6 and Lydia, 4, were adopted just three months ago from Ghana. Beckie tries to balance her desire for attachment with all the children with the firmness required to discipline them. Eddie and Lydia, the newest family members, grapple with frustration over still learning the English language and a great fear of the dark, since in Ghana there were real-life fears of violence at nighttime in their community. All the children feel free to run outside at will and ignore Mom, bedtime is fraught with turmoil, and mealtimes can be a battle zone. Compounding these challenges is the fact that Mom, at times, feels overwhelmed, outnumbered and at her limit, and very much on her own while her husband is away.

A tough New Jersey cop and his wife find they're in over their heads when dealing with four-year-old triplets and their older brother, Timmy, who's 11. The little ones pester their big brother, destroy things, and run out of the house unsupervised. Dad says, "We have three animals!" The parents think that time-outs don't work, so Mom's method of discipline is to lock the kids in their bedrooms while they scream, and Dad's method is to surrender. Mom is at home full time with the children while dad works, and when he comes home, he's on duty while she heads off to her own job. The relationship between Timmy and his father has deteriorated since the triplets arrived.

The Froebrich parents get no respect. Erich and Beverly have 5 children ranging in age from 1 to 11 years old, and admit they need a Supernanny intervention. The Froebrich children smack, pinch, yell, fight and talk back, and homework is a battleground in which Mom brings her 11-year-old son to tears. Beverly's mom lives with the family since Beverly's dad died, and she considers her daughter a control freak; the stress for everyone has gotten worse since the death. Mom doesn't discipline the kids at all, but Dad will smack the children with a wooden spoon, pull their ears, and put hot sauce on their lips -- but neither parent's approach works.

Sylvia and Michael Federico have three boys, ages 2, 3 and 5. Mom openly admits she wants to be the fun mom rather than a disciplinarian. Both parents bribe the kids with junk food to get them to behave or to otherwise appease them. Mom brings a loaded backpack with sugary snacks when she takes the boys out in public to use for bribes if they misbehave or complain. The kids sneak snacks all day long, and the parents baby the children, especially Dominic, the 5-year-old. They brush his teeth for him, pick out his clothes and let him use the stroller at will, instead of his 2-year-old brother.

Because her own mother passed away from cancer, Supernanny Jo Frost can certainly sympathize with the Evans family children who lost their mother due to the disease. The father of the three young boys is doing his best to parent them on his own and as their mother would have wanted, but the whole family finds its situation overwhelming. Can Jo help this family settle into its new shape?