Prompt: But what colour should it be?

The sun is is yellow the sky is blue,

And as soon as I look at you I knew,

It couldn’t be purple or yellow or green,

Or marigold blossom or cherry supreme,

I close my eyes and think of the trees,

I really don’t know what colour it should be,

I open my eyes and take a look,

At my Dad, Mum and my best friend Brooke,

They all look up at the clear blue sky,

Where I spot an arch forming up high,

It should not be one colour or two or three,

It should be many like a rainbow should be.