Set in Pasadena, California, Avery Jennings' mother, Ellen, had just married Tyler and Chloe James' father, Bennett, so now the new family needs to make some adjustments on living together. They face an even bigger adjustment when they discover that their new dog, Stan, can talk. Only Avery, Tyler, and Chloe know this. Unbeknownst to the family, Stan also has a blog where he discusses happenings in the Jennings–James household. The children learn of Stan's talking ability in the first episode and agree to keep it a secret from their parents, fearing if the world finds out that Stan can talk, he will be taken away for experimentation.
The main characters, from left to right: Avery, Bennett, Chloe, Ellen, and Tyler.
Avery Jennings (G Hannelius) is the highly intelligent, hard-working step-sister of Tyler and Chloe. She hates the fact that Tyler feels everything has to go his way and that good things always seem to happen to him, such as in "Stan of the House" when Tyler books the living room as an excuse to have the school cheerleading squad come over. Avery is very straightforward in following the rules and reluctantly goes along with what Tyler does. She is very smart, an overachiever, and knows what she wants. She wants everything to be handled in an orderly fashion, such as posting sign-up sheets for the living room and bathroom. Avery is socially responsible and despises boys like Tyler, though the two do have brother–sister heart-to-heart discussions showing that, at the end of the day, no matter how much Tyler annoys her, they love each other. She did not always love to take risks, but this changes when she steals a large pig in one episode. Avery is a very good problem solver and is the school president.
Tyler James (Blake Michael) is the popular brother of Chloe and step-brother of Avery. He seems to get by with his good looks, adding to Avery's jealousy, often causing the two to fight. Manipulative and occasionally a little vain, good things always seem to happen to him; he can get any pretty girl to go out with him and is extremely charismatic. Tyler is a math genius, found out later in the first season, and although he is very smart, Tyler is slacking off in school due to laziness, but in "Stan of the House" he learns he needs to act more like a brother toward Avery and will, on some occasions, show his soft, serious, and mature side. Although he can sometimes be shown to be carefree and too laid back, Tyler will rush to a person's side when they need help, showing that he cares about people and is not at all judgmental or a bad person, as seen in "Stan of the House" when he comforts Avery after she breaks down crying over losing Stan. He can also be shown to be a little air-headed, but he has a quick wit and, like Avery, he knows what he wants and he will not stop at anything to get it.
Chloe James (Francesca Capaldi) is the younger sister of Tyler and step-sister of Avery. A running gag in the show is that the family will go somewhere and forget to bring Chloe home, and when they realize their error, they scream her name at the same time. Chloe is known to love candy, though her parents do not allow her to eat too much. She secretly hides sweets around the house in places like pillow cases and TV remote battery compartments. She has a very active imagination, making up new names for various body parts and scares Tyler while he sleeps.
Bennett James (Regan Burns) is Tyler and Chloe's father and Avery's step-father. He is a child psychologist who often acts immature and childish himself and is the author of several books in which he uses his family as examples, only changing the names. He always tries to think of ways to get his children to come together. He is also shown to be quite conceited. Sometimes his wife thinks he got his psychology degree online as his attempts at practicing psychology do not seem to go well. In "Stan of the House", he introduces Stan to the blended family in hopes that the dog will help his children bond.
Ellen Jennings (Beth Littleford) is Avery's mother and Tyler and Chloe's step-mother. She does not like dogs and makes it known that she does not like Stan; however, by the end of Howloween, she and Stan get along. It is later revealed that she dislikes Stan due to an incident with a dog she had adored who suddenly left her. Due to this, she is reluctant to bond with Stan. She loves making jokes, often followed by her catchphrase, "Good one, Ellen!" She has been married to Bennett long enough to absorb some of his habits, including being scatterbrained. This could well account for their constant forgetting about Chloe. In Who's Training Who? Ellen hires a master dog trainer to keep Stan off the couch. Ignoring the trainer by daydreaming, Stan ends up outside until the children convince him that he's one of them, and he gives in and accepts the new dog bed Ellen bought him.
Lindsay (Kayla Maisonet) is Avery's best friend. Lindsay's unique quality is that she always wears a hat, even when it's inappropriate. Lindsay often talks fast when she panics, often leading Avery to also talk fast. Except for her lack of intelligence, she has much in common with Avery. They love the same books and movies and often say the same things at the same time involuntarily, and she also dislikes Karl just like Avery. However, Avery dislikes Karl more than she does. In Avery B. Jealous, Wes, Avery's crush, asks Lindsay out on a date. Lindsay promises Avery that she will call off the date, but when they get in a fight, she decides to go out with Wes. Lindsay admits that she has always had a crush on Wes. In Avery-body Dance Now, she and Max confront Wes when he turns Avery down on an invite to the school dance after Karl tells Wes he is going with Avery.
Nikki Ortiz (Denyse Tontz) is Avery's friend and Tyler's current girlfriend. She has a dog named Evita, who Stan despises because she yaps too much. Nikki moved from El Salvador and is sweet and talented. In Wingstan, she is shown to be great at whistling and art. In Avery's First Crush, Nikki accidentally reveals her confusing and mysterious secret: "My brother didn't fall. He was pushed." In Love Ty-Angle, she becomes jealous of Tyler's girlfriend and is confused about it. Nikki asks Tyler to dump Emily for her, but since he can't trust his dream girl, he chooses Emily; however, she learns about Nikki's pursuit of Tyler. This leads to Tyler being broken up with by Emily and, despite never being picked second for anything, Nikki accepts when Tyler chooses her.
Karl Fink (LJ Benet) is Avery's frenemy. He and Avery are the smartest children in school; however, in contrast to Avery, Karl is a shameless jerk. Being very nosy, he often barges into the Jennings–James house without knocking. He also tries to find out Stan's secret in The Bone Identity. He despises Avery because when they were much younger, she stole his graham crackers at a science camp. He often has tea and snacks with Ellen, much to the discomfort of others, though they both claim that it's not weird. He once admits that he likes to send Ellen flowers under the alias of Walter Perkins. Karl has mentioned several times that his father is up on the International Space Station and talks often about his obsessive bodybuilding mother, who he says is the strongest woman in the world, though she has never been seen on the show. In Avery-body Dance Now, he teaches Avery how to dance for the school dance with Wes; however, he tells Wes that he is going to the school dance with Avery. In Karl Finds Out Stan's Secret, it is revealed that Karl has been spying on Stan and the children for a while. Now he knows that Stan can talk, but keeps it a secret.
Max (Danielle Soibelman) is one of Avery and Lindsay's best friends, as shown in the second season. She is shown to be a very negative, but overall nice, person despite sporting dark clothing. She likes to act tough and says she hates everything, but she also dances with Karl at the school dance.
Wes (Peyton Meyer) is Avery's crush in the second season. In Lost in Stanslation, Avery acts as his Spanish tutor; at the end, he asks her if it would be inappropriate to ask her out on a date in Spanish, but since she does not actually know the language, she answers yes in Spanish. He is very upset as he had said he wanted to ask her that even before she was his tutor. In Avery B. Jealous, Wes asks Lindsay out after being rejected by Avery, but in the end he says that he is glad that he isn't going with Lindsay as he wanted to go with Avery all along. In Avery-body Dance Now, he asks Avery to go to the school dance with him; however, when Avery seeks dance lessons from Karl, Wes becomes jealous of Karl, and when Karl tells Wes he is going with Avery, Wes goes by himself. After Lindsay and Max witness Wes' anger at Avery and Avery running out of the dance in tears, they learn of Karl's deception. Wes goes to Avery's house, where he tells her he likes her, and they return to the dance together. In The Green Eyed Monster, Stan accidentally captures a photo of Wes with another girl in the park, and Avery confronts him, which causes a temporary problem between her and Wes as he tells her he can't date a girl who doesn't trust him, but Tyler and Stan get together to convince Wes it wasn't Avery's fault and that she just has strange relatives. In Love, Lose and a Beanbag Toss, Avery notices that Wes is ignoring her; after several confrontations he finally tells her that his family is moving to another city. They both agree on a long distance relationship through the Internet, but soon notice that it is not going to work out well. They then decide to end their relationship and try to move on.
Mason (Griffin Kunitz) is Chloe's current boyfriend. According to Chloe in Stan Gets Schooled, Chloe and Mason started their relationship because Chloe came up to him, said "You're my boyfriend!" and gave him a tongue click. It is shown in Stan Has Puppies that he has twin brother named Jason.
Heather Collins (Brighid Fleming) is Princess' owner and the Jennings–James' next-door neighbor who moved in with her family in Stan Falls in Love. She is shown to be spoiled, ridiculously snobby, and stuck up. She also seems to have a liking to Karl.
Dog with a Blog has received generally mixed reviews from critics. Critic Brian Lowry for Variety gave the show a mixed review, saying that "young kids should enjoy hearing Stan express dog-like thoughts", but concluded that "Dog with a Blog is strictly low-hanging-biscuit fare".Common Sense Media gave the show two stars out of five, calling it a "so-so sitcom" with "lackluster writing and cliche humor" while praising it for having "some heartwarming messages about families".
The series is co-created by Michael B. Kaplan, who previously co-created the Disney XD series I'm in the Band. Stephen Full was previously a cast member of that series, along with Beth Littleford who had a recurring role. G Hannelius and Regan Burns also previously guest starred on I'm in the Band during the show's two-season run. On February 4, 2013, Disney Channel renewed the series for a second season. On February 4, 2014, the series was renewed for a third season by Disney Channel.
A spin-off short series called Dogs Rule! Cats... Not So Much debuted on Watch Disney on February 14, 2014. It is a variety show hosted by Stan comparing dogs to cats and showing various dog or cat Internet videos. The spin-off commonly airs on Disney Channel during commercial breaks.