My Son Is 8 And Taking 10 Mg Of Vyvans

My son is 8 and taking 10 mg of Vyvans 7:30/8:00 am. Works well. He also takes a chewable multi vitamin with fluoride, two gummy omega fish oil at dinnertime with meal. Should he take his vitamins in morning or is it best to keep them separate? Would 1ml of b complex be good to put in his juice afterschool or is that not necessary?