Cowan & Kelly Attorneys Langhorne PA Probate Attorney | Levittown Pennsylvania Estate Planning Lawyer | Bankruptcy Real Estate Bucks County Are you in need of a knowledgeable attorney? At the law office of Cowan & Kelly, we serve clients in Levittown, Philadelphia and throughout the surrounding area from our Langhorne, Pennsylvania office.. Call us today at 215-741-1100 to speak to an experienced lawyer.