Discount brokerages require a minimum age of 18. However, you can create a sub-account under your dads name (as long as he signs some sort of consent form) and these sub-accounts don't have a minimum age requirement.
Vitamin D deficiency rickets can be caused by a lack of vitamin D in the diet, a lack of exposure to the sun, or malabsorption syndromes in which there is an inability of the intestines to adequately absorb nutrients from foods.
Low vitamin D has long been linked to depression. Experts now believe a lack of vitamin D might also contribute to other mental health problems such as personality disorders and post-traumatic stress disorder, according to The Sydney Morning Herald.