New here with a small bird identification question

Hi All, I'm from Fareham on the south coast of Hampshire.

I'm trying to engage my children (2 and 4) and we have had a new visitor to the garden that I can't quite place

Thought it might be a Chiffchaff or a Willow Warbler but the beaks wrong. Looks more Finch like

It looks very light and almost Sandy?