
They are probably getting enough 'liquid' from their food at the moment especially if you are feeding it in a porridge consistency. I can't remember when mine first started to show interest in the water, but as advised, you should always provide a shallow dish of water, once they are onto solids. I never leave a dish in the box overnight. Just in case.
And mine would have a mid-morning, mid-afternoon and last thing drink of warmed goats milk - all liquid so making the need for water less. And initially with weaning, most of their nourishment would still be coming from mum. So it would really only be later on that they'd actually NEED water.