cherry, feelin better after rantin out? Is it a norm for both ur fil n mil to wash hands upon reachin ur place? Did u mention to them b4?
Ur mil is total opposite wif mine lor. Mine wont give Yakult or any nonsense stuffs to T totally. So last time once T takes a little bit of snacks or cold drinks den confirm will fall sick liao coz his body is not "adjusted" to takin snacks. Now I give him a little of everything, makin sure he drinks loads of water after eatin. Perhaps u can ask ur hb to inform his parents not to give Yakult or snacks to ur kids. Keep naggin at ur kids dat they shld drink more water after eatin the snacks. Try not to b the 1 "slashin" out at ur in laws for givin those nonsense stuffs. 1 thing to note - Be glad u r not stayin wif ur in laws.
As for ur mum, perhaps she still not used to givin orders lah. My old hag at home used to "listen" to maid also. Stay cool for now & try not to let it affect ur mood for rest of the day.
Take a deep breathe though I noe sometimes its really hard to control the "fed-up-ness" inside us. 
Ur mil is total opposite wif mine lor. Mine wont give Yakult or any nonsense stuffs to T totally. So last time once T takes a little bit of snacks or cold drinks den confirm will fall sick liao coz his body is not "adjusted" to takin snacks. Now I give him a little of everything, makin sure he drinks loads of water after eatin. Perhaps u can ask ur hb to inform his parents not to give Yakult or snacks to ur kids. Keep naggin at ur kids dat they shld drink more water after eatin the snacks. Try not to b the 1 "slashin" out at ur in laws for givin those nonsense stuffs. 1 thing to note - Be glad u r not stayin wif ur in laws.
As for ur mum, perhaps she still not used to givin orders lah. My old hag at home used to "listen" to maid also. Stay cool for now & try not to let it affect ur mood for rest of the day.