Thanks guys. As it happens the bearings are fine – I re-greased them recently. However I believe the noise that is coming from my BB may be because one of the dust covers is falling apart. Don't s'pose you can buy then separately.
My eldest was 5… went like a rocket once they were removed.
My second is now 4 and we did recently (2 months ago) remove his stabilisers. However they have now gone back on as it turned out he was a bit scared of his bike without them…
Found the Stickler this morning. Went to the end of TT and cycled all the way up to the start of Sticker. Now I know where it starts. That makes me happy.