Help me find this kid's book?

[pooopypants]

I've tried Google but I'm stumped.

Kid's book - early teens I believe
Group of kids, they sounds upper middle class as I remember
They befriend a circus (?) boy who has a pet monkey (Barney? Barnaby?)
They solve mysteries

I thought it was Enid Blyton but I can't seem to find the books when I went through her list (700+ books!) and considered Famous Five and Secret Seven.

Any and all help gratefully received!!

The Barney Mysteries by Enid Blyton.

https://en.m.wikipedia.org/wiki/TheBarneyy_Mysteries

I remember these! They are Enid Blyton, and they are called 'The Barney Mysterys'

Could it be The Barney Mysteries by Enid Blyton? The monkey was called Miranda but there was a character called Barney.

Cross posts with everyone

Was there an angry circus worker called Tonnerre (thunder)?

And did they tie a stone to a piece of rope to get the monkey to carry the rope up somewhere ...?

Miranda - yes! And yes, one of the more concrete memories I have is about that stone on a rope being wound through some bars on a window.

Off to Amazon we go.

You lot are fricking awesome!