In Tom's Midnight Garden, the concept of freedom evolves from the overwhelmingly childlike and whimsical sense to the incredibly existential interpretation of freedom. At first, it is the story of a child who is quite used to physical freedom. He becomes constrained due to a risk of measles. Tom must move from the large house of his parents to a small flat with his Aunt and Uncle. Most glaringly, the apartment has no yard in which to play. The restriction on his freedom makes him restless, which causes him to discover the garden.
When Tom discovers Hatty, the two find an extraordinary freedom with each other, away from their somewhat distressing family lives. It becomes quite clear that the levels of oppression forced upon them is disproportionate. Not only is there a time gap between them, but one of gender as well. Hatty has obligations forced upon her that Tom can barely begin to understand. This is represented by Hatty being forced to actually grow up as time is relatively still for Tom. This progresses throughout Hatty's life until finally we realize that her final incarnation is Mrs. Bartholomew, a woman who, though realized, is still trapped in her tenants' perception of her. However, she is far less trapped in the urban world than she was in the Victorian one. Perhaps it is partially owing to her meetings with Tom that occurred over the course of her life.