SusanPHi,
Our daughter also had a few long hairs around 7 with no other precocious puberty symptoms. We didn’t worry and just kept watching her for breast buds. They started around 10. She’s 11.5 now and still no menstrual cycle while many of her friends have already started. I might push for some testing, but really wouldn’t panic without other signs such as growth spurt, acne, greasy hair or breast buds. Go with your gut feel; good luck.