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Ron's mother, Molly Weasley, immediately welcomes Harry into her home. She is the first really mothering figure that Harry can remember meeting. Compared to the Dursleys, she's an absolute domestic goddess: she does yell when her sons break the rules, but there is an underlying core of immense love in everything she does.
Ron's relationship with Mrs. Weasley provides an interesting contrast to Harry's own situation as an orphan. When Ron and Harry drive their flying car to Hogwarts, Mrs. Weasley sends a Howler that explodes furiously over the Gryffindor dining table at breakfast:
– STEALING THE CAR, I WOULDN'T HAVE BEEN SURPRISED IF THEY'D EXPELLED YOU, YOU WAIT TILL I GET HOLD OF YOU, I DON'T SUPPOSE YOU STOPPED TO THINK WHAT YOUR FATHER AND I WENT THROUGH WHEN WE SAW IT WAS GONE – . (6.17)
Mrs. Weasley's scolding leaves Ron and Harry both feeling sick with shame. Mrs. Weasley reminds Ron of the consequences of his unexpected adventure: Mr. Weasley is facing an investigation at work for his own misuse of a Muggle artifact. Mrs. Weasley has a hot temper and she's a strong figure of discipline in Chamber of Secrets.
At the same time, we also get to the see the flip side of her highly emotional relationship to her children. When Harry and Ron appear at Professor McGonagall's office having rescued Ginny, Mrs. Weasley, face streaked with tears, immediately throws her arms around her daughter. She then embraces Harry and Ron and says, "You saved her! You saved her! How did you do it?" (18.5). Mrs. Weasley may get angry when her kids do stupid things, but all of her temper comes out of love.
Now, J.K. Rowling has commented on Harry's own orphan status:
I think that's definitely true. Harry's status as orphan gives him a freedom other children can only dream about (guiltily, of course). No child wants to lose their parents, yet the idea of being removed from the expectations of parents is alluring. The orphan in literature is freed from the obligation to satisfy his/her parents, and from the inevitable realization that his/her parents are flawed human beings. (source)
Harry can go off after Voldemort at every turn because he doesn't have a Mrs. Weasley around to send him Howlers and worry if he's going to be killed. Well, we mean – he does have Mrs. Weasley, since she's like a surrogate mother to him. Still, there's no one in Harry's life who has the kind of authority a parent would have over his actions. Harry's orphan status and reckless nature allows him to blunder into things that other characters can't. While we love Mrs. Weasley, it would be impossible for Ron to be the hero of the Harry Potter novels because of her enormous influence on his life. Harry's isolation in the world is what makes him hero material, according to J.K. Rowling.
Even so, while we follow Rowling's logic, that lack of discipline or authority also leaves Harry without someone to cry over him when he's in deadly danger. When Harry lay in the Hospital Wing at the end of Book 1, there was no Mrs. Weasley to sit by his side. That's really tragic – Harry's freedom comes at the cost of his family life.