When my son was little, just before heading on a drive we would fill his sippy cup with ice cubes, and put in about 1/2 inch of water. This kept him getting sips of water for the whole trip, and prevented any major spills from happening. Also, in a carseat, a child's little 'sit-bones' tend to get sore very quickly. A gel-pad that you can get at a bicycle shop will make the journey much more pleasant for everyone.
By: sedim
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Keeps the Kids EntertainedTravel Sickness, Cleanups, and Laptop Entertainment
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Memory Making
Leave the Noisy Toys at Home
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ID for the Kids
How Not to Lose Your Child?