Hi, glad you made it in okay :)
What is meant by the term holistic development - this is all areas of development, seeing the child as a whole unique individual.
For more information this thread may help
https://www.silkysteps.com/forum/showthread.php?t=21314
As development is different for one child to another eg. for physical development one child may walk at 12 months old another walks at 18 months old, both children are considered 'normal' and fits within a pattern of expected development ie. sits up unaided, maybe crawls or bottom shuffles, stands up unaided, walks, runs, jumps and hops.
You will need to research holistic/all development, has your tutor recommended a handbook to help with this?
This
handbook has useful information for development (but may not be linked to your course) search inside the preview on amazon for the words 'expected development' and click where it says page 46. Page 232 explains interdependency.
This
child development book is also good reading, it's possible your setting has a copy you can ask to borrow.
Forum thread on child development
Best wishes xx