Patricia P. McKenna     PORTLAND - Patricia P. McKenna, 50, died on Feb. 2, 2006.     Born in Portland, she was the daughter of Byron Mitchell and Pearl Mitchell.     She was predeceased by her father and brother, Adam Joseph, and is survived by her mother; five daughters, Laura, Kathy, Amy Darla and Christy McKenna; five grandchildren, Matthew, Cody, Mackenzie, Olivia, and Amber; and her fiancŽ, Gerald Webber of Limington.      A celebration of Patricia's life will be held at the Presumpscot Grange at 1844 Forest Ave., Portland, on Feb. 11 at 1 p.m.     Arrangements by Independent Death Care of Maine.