Chapter 27 of The Secret Garden includes pretty much everything you wouldn't expect based on the previous twenty-six chapters. For one thing, the chapter appears mostly from Archibald Craven's point of view, even though he has been largely absent for the rest of the book. We follow him as he reads Susan Sowerby's letter and dreams of his wife, thus sending him back to Misselthwaite Manor.
We also finally get some insight into Archibald's terrible behavior towards Colin: "He had not meant to be a bad father, but he had not felt like a father at all" (27.29). As the novel explains his dark heartbreak over his son's poor health and weird resemblance-but-not to Lilias, it builds up some degree of sympathy and understanding for the man who has spent most of Colin's life fleeing his fatherly responsibilities.
In addition to giving us some much-needed Archibald backstory, the final chapter of the novel also continues its later theme of Magic.
In some ways, the chapter reads less like a piece of fiction and more like the conclusion to a thesis statement on how Magic connects people spiritually. Just as Colin is announcing in the Secret Garden, "I am going to live forever and ever and ever!" (27.10), Archibald finds himself in a Swiss valley meditating over a particularly clear pool of water. As he sits calmly, he thinks to himself, "I almost feel as if—I were alive!" (27.8). The unbreakable link between father, son, and the power of nature all wake Archibald up to his need to get home to Misselthwaite Manor to meet his son properly.
As Archibald approaches Misselthwaite Manor, the novel nicely builds up what suspense there can be when we know that there's probably going to be a happy ending. Archibald wonders if it's too lateto look after his son, while we all know that his son has been looking after himself, and once he arrives, Mrs. Medlock is so full of conflicting stories and uncertainty that it only confuses Archibald further.
But as Archibald goes out to the long-lost garden he shared with his wife, Colin comes running straight into him. Colin has just won a race, and he is so happy and triumphant that his meeting with his father just feels like the frosting on the cake. And when Archibald sees Colin, he realizes that he is "a tall boy and a handsome one […] glowing with life" (27.61). Colin volunteers to walk through the garden and back to the house with his father, thus finally revealing to the household staff that he does actually know how to walk.
And so all is right with the world—right?
Yeah, we've got a happy ending here. But as we have griped elsewhere in Archibald Craven's analysis over in the "Characters" section, it seems a little weak that he gets a free pass from the novel and his son despite ten years of intense, neurotic neglect. The novel paints such a dark picture of Colin's early life that this quick conclusion of a Magic-healed Craven family feels a bit abrupt.