Advanced Bone Age and its Effect on Height

My granddaughter was recently diagnosed with advanced bone age. She was 7 years old at the time of the test
and her bone age was advanced by 1.5 years. She also has begun to sprout a few underarm hairs. These are
her only "symptoms." Her estrogen levels are fine, only the androgens are affected, and blood work was
recently done although results are not in yet. The specialist told my daughter (her mom) that there is a
good chance she will stop growing prematurely, maybe only being 5'3". Her mom is 5'9" and her dad is 6'0"
and everyone else on both sides of the family is tall. We are all quite upset about this, not knowing if that
prognosis is accurate or even optimistic. I would appreciate any information you could share. Thank you.