Noah isn't nursing right now but I remember that nursing during holidays the past two years always brought a lot of anxiety for me.
Relatives asking..."when are you going to wean?" or "are you sure you need to feed him again?"... etc.. etc. Besides the fact that its not always the most comfortable situation trying to nurse in front of a BUNCH of people who are close to you especially if they aren't familiar or supportive of breastfeeding.
And sometimes... older babies are too distracted by all the chaos to actually settle down and nurse.
My advice.... find a quiet place to nurse and make sure you tune into your baby's needs when they start to fuss instead of letting relatives tell you why they are upset or why they aren't. BREATHE.... mostly.. just breathe. If you can't relax, let down isn't going to happen very quickly.
Here's some useful links I found for nursing during the holidays
Beware of Holiday Weaning
Handling Criticism about Breastfeeding
Nursing past 1 year?!
Nursing Mother's Guide to Surviving the Holidays