6 year old ds had communicating hydrocephalus as a baby/toddler but has been stable for nearly 2 years. He has vomited randomly about once or twice a week for the last month or so. No runny poo, doesn't seem ill. School insist he stays home for 48 hours after each vomit but moan about his attendance. I have contacted his paediatrician but she is on holiday. Has anyone else experienced this?