Without wanting to worry you, my DS now 13mths and forward facing in the car STILL cries/whinges/screams if driven longer than 10-15 minutes. He has been like this since a tiny baby, doesn't matter which car seat or car although is better with someone sitting beside him in the back. Just wanted you to know that you are not alone and for some children this is normal. Also, he never sleeps in the car unless ill!!!
I have tried many different above mentioned (and other) techniques to improve the situation but TBH he really only calms down when we stop and he gets out. While I don't like him to cry I still go out in the car all the time as I would be driven mad if stuck at home. We won't be taking any road trip holidays in the near future though!
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