The sequence of development is the order in which things develop - one after the other, you must finish with one area of development before you move onto the next one. For example the Cephalocaudal principle believes that development moves from the head downwards. It understands that infants get full control of their heads first, then their arms and finally their feet, from top to bottom. The understanding is that the spinal cord needs to develop properly before other areas such as the hands and feet and then fingers and toes develop. This is sequential and you cannot skip sequences or you will not be fully developed.
The rate of development is the ‘speed’ that a child develops, this can be the speed within each sequence or the speed overall.
So the difference between the sequence and the rate is that the sequence usually remains the same whilst the rate usually changes. The rate can be different in every child due to factors such as their background and upbringing, their nutrition and health and learning difficulties or disabilities. These can however effect the sequence of development as if a child has disabilities it tends to have an uneven sequence of development, if one is skipped or slow whilst growing and developing it can be a cause for concern and be early signs of a disability or health issue.
It is important to know the difference between sequence and rate as a child that’s rate of development is a bit ‘slow’ can be perfectly fine and just a part of how the individual is, whereas a child who’s sequence is slow or skipping parts may be suffering from health issues or disabilities.
Growth and development are a continuous process and are different for all