metrocksncn - Muscle size is definitely not a factor in neck pain. I would suggest working on the posture (erector set) and upper back muscles (rhomboids/traps).
For years I had neck pain, despite a 20 inch neck, and worked the 4 way, etc. I recently learned I have extremely loose muscles, and needed tension in those muscles to develop better posture and support my neck and moon sized head.
Started lifting heavy 1-2 days a week (roman deadlift, deep squats, high pull), quest barbell interval 2 days a week, and did shrugs/one arm cable pull/close grip pull down every day (bands and machines).
Posture and neck problem solved with 30 min a day within a month...Bonus if you like the squatters butt that she develops.