As often as I have to say no to my 3 children over the past few months, it has made me realize that we need to work a little funny money into our monthly budget. Call it what you want, I heard it referred to as many different things on PF blogs, couples call it the his/her fund, guilty free fund, etc. You need to factor in a little funny money into your budget to be spend on entertainment or a personal purchase each month.
If the budget is truly that tight, then this would be one of the first things that would need to be cut. There are a number of free or low cost things that can be done with a family. Library trips, park trips, etc. If your budget allows sent a limited and stick to it. The money can be used for movies, eating out, gifts, a night out with friends etc. Having it within your monthly plan is the key, it will limit you from the unexpected and from over spending. It will also keep everyone happy.
Do you have funny money built into your budget? If so what's the amount/ rules around it?