Join the celebration as Chestnut Knoll marks its 26th anniversary with a birthday bash on Wednesday, Sept. 23, at 6:30 p.m., at 120 W. Fifth St., in Boyertown.   Enjoy complimentary cupcakes, refreshments, and entertainment from the talented Boyertown Alumni Ceremonial Band. All attendees will be entered for a chance to win a raffle basket. Come and see why our award-winning Personal Care and Memory Care senior community is such a special place to call home. RSVP by calling 610-473-8066 or emailing JKrasley@chestnutknoll.com.   The concert will be held outdoors and is open to the public. If inclement weather occurs, the concert will be moved indoors; however, attendance will be limited to residents and their families only.