Being a photographer I know how important it is to have your families portraits taken or in a photographers case; every new outfit that is purchased, every tooth that falls out, every haircut or nap time, but let's be realistic here, not everyone has the knowledge of a photographer to document all of this. Here is an idea of how often you should at least have your family photographed.
ONCE A YEAR at minimum. Your kids on the other hand are another story, they grow so quickly and have many milestones that should be documented, especially when they are really little.
So then how often should my kids be photographed?
Newborn - 1: I would say 5 times maximum. So newborn and then every 3 months there after; now obviously I know this may not be feasible for a lot of families so what I recommend is check with your photographer and see if they have what is usually called a milestone collection. Typically this collection will be discounted simply because you are committing your business to them for your child's entire 1st year of growth up front. Photographers are aware of how quickly your child grows and changes just in that first year and they want to make sure they can document that for you. If the photographer does not offer this then be on the look out for what is called a mini session, these are quick 15-20 minute sessions that are also offered at an affordable rate and would be great for milestone shots.
Age 1-2: For this age I would recommend at least 2 times, one 6 months after their first birthday and then of course their 2nd birthday. This age your child is still changing quite a bit, but not nearly as much as that first year. I would then do the same for age 2-3 and 3-4.
Age 4 and up: This age your child is still growing, but not nearly as quickly as say a baby in their 1st year so for this age I would recommend a minimum of once at that family session. Other milestones that are wonderful to document are when they are 16 and then again when they are seniors in high school.
Now that we have established ages and frequency then working out a budget to have them photographed should be easier. Decide the route you want to take as far as custom portrait photographer or something as simple as going to a big box store. If you are surfing the internet and looking at custom photographers I would suggest keeping the thought of money in your back pocket. If your budget is tight try to start your research at least 6 months before you would like to have the portraits taken. This will allow time for you to put the money aside for the images you will really love. If you are choosing someone to capture those sweet moments that will be passed on for decades you better damn well like the work. Look at the photographers portfolio and bookmark the photographers work that really speak to you, find out their prices and don't think about that price as what you are going to spend now, but something you will spend in the future.
We all know life gets busy and having portraits taken is usually not number one on the list, but it should be. Write it on your calendar just like those weekly baseball games and play dates, memories should never be put on the back burner.