The most effective way to exercise for fat loss is to create a program that combines high-intensity and low-intensity exercise. Thatâs because each type of exercise promotes fat loss in different and complementary ways.
Since you asked, I do think it is odd that your grandchildren sleep with you if you have other accommodation available for them. Also, a nine-year-old should be able to bathe or shower alone. I would worry more about lack of independence at that age than anything improper, but at age 9 I would expect a boy to be more modest than you are describing.
The National SAFE KIDS Campaign recommends that children not be left alone before the age of 12. Many other children will not be ready until later than that. Also, experts caution that older siblings are generally not ready for the responsibility of supervising younger children until the age of 15 or older.