Need help with Pedigree question?

linked (100 % of boys have it so it is on the mother's X chromosome) and is recessive in girls so only a girl who inherits it on both X chromosomes-one each from father and mother-- will have the disease) but girls who inherit it on one X chromosome will be carriers. Terry is a carrier and unfortunately both her sons got her X chromosome with the mutated gene for muscular dystropyhy.