My Sister Went To The Gyno...she Has Fibroids...one Grew..the Other

my sister went to the gyno...she has fibroids...one grew..the other stayed the same...she's 51...she went one year no period..n she spotted. .one month...n next month a few days...not alot..the gyno wants her to get an endometrial biopsy done..She said it's a red flag..if she's bleeding. ..her lining went from a 5 to a 7..The doctor got her very scared...no other signs of bleeding...she got bloodwork to check her hormones..Shes waiting on the results for that..She's soo upset. .and thinking the worst...Can stress make her have breakthrough bleeding??