“You can do it! You can do it!”
The repeated encouragement is paired in the scene with Colin’s own attempt, making confidence a support for action rather than a substitute for trying.
Source details
The Secret Garden (1911), Chapter XXIII, “Magic.” Colin recalls that when he first tried to stand, Mary repeated “You can do it! You can do it!” The represented record is therefore tied to Colin’s recollection of Mary’s encouragement, not presented as general rehabilitation or medical advice.