At Colin's instruction, Mary draws back a rose-colored curtain hanging over the mantelpiece to reveal a picture of a laughing woman with gray eyes exactly like Colin's own. Colin tells Mary that this is a portrait of his mother. It is kept covered for two contradictory reasons: on the one hand, Colin dislikes that she is laughing while he is so ill and unhappy; on the other, he thinks of her as his treasure, one which he does not wish to share with anyone. He almost hates her for dying, for he believes that he would not have been sick, and his father would not have despised him, if only she had lived. Mary tells Colin that she will continue looking for the door to the garden, and the two children decide to keep their meeting a secret. Before leaving, Mary sings him to sleep with a Hindustani lullaby that her Ayah used to sing to her.
The motif of secrets is greatly enlarged upon in this chapter in a number of ways; the secrets include the portrait of Colin's mother, Colin's room, and the person of Colin himself. The forbidden quality of Colin's bedchamber is similar to the fairy-tale story of Bluebeard and his wife. Like Bluebeard's wife, Mary finds her own curiosity irrepressible. She does not, however, try to repress it: her contrariness inspires her to disobey all prohibitions.
The similarity of this scene to a fairy-tale is borne out by the way in which neither Colin nor Mary is certain at first that the other is not a dream; this blurry distinction between fantasy and reality is, in some sense, the definition of a fairy story. The question of whether this is all a dream also arises, in some measure, because both Mary and Colin are awakening from a long sleep: their meeting (particularly for Colin) heralds their complete re-awakening. As Mary remarks: "It looks quite like a dream...[because] everybody in the house is asleep-everybody but us. We are wide awake."
The first meeting between the two children makes it quite clear that they have lived what might be called parallel lives: both are precisely ten years old; both were burdened with parents who could not bear to look at them; both have passed sickly, neglected childhoods that have left them unbelievably spoiled; and both have been denied and hidden away like secrets by the parents. Upon seeing Colin, Mary exclaims, "I never knew [Master Craven] had a child!" This outburst precisely echoes the reaction of the British soldiers upon discovering Mary in the bungalow.
The fact that both children have been kept as secrets explains why they determine to keep their meeting a secret, and why the idea of a secret garden is so appealing to both of them; the latter is even attractive enough to inspire the spoiled Colin to be patient. When one is a secret, one is not able to keep secrets of one's own; the fact that Colin and Mary now share this one indicates that they are acquiring a new power and independence.
It is important to note, however, that Colin has at least one other secret: the portrait of his mother that he keeps concealed behind a "rose-colored" curtain. The curtain continues the association of the Mistress Craven with roses, and also further aligns her with the secret garden; she, too, has been "shut away" for the past ten years. As in the case of the secret garden, it is love of Mistress Craven that partially inspires the concealment. As Colin says, "She is mine and I do not want everyone to see her."