- Mary arrives at Misselthwaite unable to dress herself. And in the case of the 1993 film it's clear that she genuinely doesn't know how (she can only put on boots and wander around the house in her nightgown). But she spent however long on a voyage from India back to England. How did she get dressed every day?
- It is possible there were servants on the boat taking care of the children. In the 1993 film the relatives picking them up do seem to be grandly dressed, so they're clearly middle-upper class. Mary may have had some remaining servants on the boat with her that didn't get taken to Misselthwaite - Medlock wouldn't want another extra person to take care of, especially if she was expecting Mary to be sent off to boarding school soon.
- In the 1993 film why does Mary act surprised when Colin suggests they marry? Cousins married all the time in Victorian times.
- Aside from the obvious Values Dissonance (as the movie was aimed at children) cousins generally married in country regions - where there were less people around. As Mary's family were City Mouses to some extent - throwing fabulous parties all the time - Mary probably would have had more opportunities to marry than Colin. She might not have even been educated that cousins can marry - it's not known the extent of what her education was in India - so she may have assumed that cousins couldn't marry because they were already related.
- Why isn't Mary sent away to school? And why isn't she having any education at Misselthwaite?
- Medlock pushes Lord Craven to send her to boarding school - but that's mostly because she doesn't want to have to entertain the girl all day herself. But when Mary meets with her uncle, she asks to be allowed to stay at Misselthwaite (because she wants to be near the garden). If she didn't go to school, then a governess would probably be hired for her. It's just that Lord Craven hadn't got around to arranging one. Presumably once the thrill of reconnecting with Colin dies down, he'll hire someone to tutor the children.
- In the book, Medlock doesn't have to entertain her at all, and never pushes for her to go to boarding school. However, Mary tells him that she does not want a governess yet because she prefers to spend her days outdoors, and he tells her that Martha's mother stopped him on the moor and gave him the same advice (no governess and lots of time spent outside until she becomes stronger). Boarding school is never brought up.
Headscratchers / The Secret Garden