The next morning, Mary sleeps late and then listens to Martha as she eats breakfast. Martha says that Colin is quiet, but feverish and worn out from his tantrum. He wants to see Mary, and Martha compliments Mary on how she handled Colin last night. She's astonished that Colin actually said "please" when he asked her to fetch Mary for him this morning. Mary decides to go see Colin before heading out to the garden. She tells Colin that she has something to tell him about the garden later and then runs outside.
The drastic change in Colin's manners illustrate the effectiveness of seeing oneself in a mirror, even if that mirror is another child: by witnessing Mary's own selfishness, Colin is willing to evaluate how he treats the staff. By deigning to see Colin quickly before heading outside, Mary shows that she also learned something last night too: the power of making Colin feel seen and heard.
In the garden, Dickon introduces Mary to two squirrels, Nut and Shell, who ride in his pockets. Mary tells Dickon about Colin. Dickon seems to feel sorry for Colin and says they have to get him outside soon. Mary responds in broad Yorkshire and explains that Colin would like to meet Dickon, so Dickon should visit Colin's room tomorrow and then, soon, they can all go out in the garden. She's proud of her Yorkshire and Dickon is also pleased. He suggests she use the dialect with Colin to make him laugh.
The novel overwhelmingly positions broad Yorkshire as something that's linked to the natural world of England and the specific region that Mary and Colin are in; it's something that helps them connect to the land and to the poor people who live there and speak it.
A bit later, Mary heads inside. When Colin asks what she smells like, she tells him in broad Yorkshire about sitting with Dickon and the animals in the sunshine. It does make Colin laugh, and Mary joins him. Mrs. Medlock stops herself from entering and is astonished by the laughter she hears inside. Mary goes on to tell Colin everything about Dickon, his creatures, and his pony. Gravely, Mary says that Dickon is friends with everything. Colin says that he hates people, but he wants to be friends with things. He admits he likes Mary, and Mary says that she, Colin, and Ben Weatherstaff are all alike.
Colin's ability to admit that he wants to befriend things (though not yet people) shows that now that he believes he's not on his deathbed, he's ready to start building a community. Through doing so, he'll gain even more people and animals to act as mirrors and help him check his behavior. When Mrs. Medlock chooses to leave the children alone, it suggests her recognition that this friendship is the best thing for Colin right now.
Colin touches Mary and apologizes for threatening to send Dickon away. He says he wouldn't mind it if Dickon looked at him. Colin sees Mary's face and knows that she's going to say something exciting. Mary stands and anxiously asks if she can trust Colin. When he says she can, Mary says that Dickon is going to visit and that she found the door to the secret garden. Colin nearly sobs. Mary tells him all about it and admits that when she told him what the garden might be like, she'd already been in—but she wasn't sure if she could trust him.
Mary's confession reinforces the importance of secrets within the logic of the novel. Sharing the existence of the secret garden's door with Colin, and the fact that she'd already been in, allows her to help Colin feel as though he's a valuable person in his own right, while it shows both of them the power of being honest.