Your best bet may be to reduce the amount of deep cleaning needed. Frequent vacuuming, not wearing shoes inside, promptly cleaning up spills, not allowing meals/snacks anywhere but at the table, etc will really help prevent the carpet from getting dirty. Food spills really do a number on the carpets, and kids are great at spilling/dropping/throwing food.
I typically clean the carpet annually, but skipped it this summer because my roommate was jobless. In retrospect, she doesn't seem to have any sense of urgency about not spending money, so I probably should've just gotten it cleaned. But it isn't bad at all. Like, if you walked in, you wouldn't know it hadn't been cleaned since summer 2015. And I have 2 cats who do things like bring in rodents/bugs, spread litter and fur all over, throw up wherever I don't want them to, etc.