Sounds like sensory processing issues.
All children learn to understand the world by sight, sound, smell, touch etc
A child who is hyposensitive, sometimes when processing things it gets muddled up on the way to the brain.
This can manifest in lots of ways... like lining up toys. Or relatively simple things like clothing feeling wrong in some way.
So this sounds like a visual issue, perhaps too many objects making it impossible to process them and turning them upside down makes it easier in some way.
Some children with autism as an example like to watch TV upside down.
Do they have a diagnosis?
Some children may seem severely behind developmentally but catch up in time and are not so much disabled as just not neurotypical and do adapt