Hi and welcome to HCM.Thank you for the query.
This is not usual sign of liver
disease and I dont think you need to be concerned. It can be sign of increased blood flow through palms or some mild skin irritation.also, some children have reddish palms norally till 6-7 years old. More prblematic may be if palms become pale and cold
. So if you want you can check his liver enymes and do ultrasound
but I dont think this is necessary at this point.
Wish you good health.Regards