My grandparents are king of negative comments about carseat safety.
First, they don't see why my 3 year old is still in a carseat at all.
They comment on how he can't see anything. How he must be uncomfortable. How he must be smashed and unhappy.
Once they said "dont worry. as soon as he can talk he'll let you know how uncomfy he is" (my son has speech apraxia and low oral tone..so, at just 3 years old, he's not at all a good talker).
The BEST one from them was this..while in the car with my grandmother... Grandmother: "wow! he's so quiet back there!..is he sleeping?" Me: "no. he's always pretty good in the car". Grandmother: "i guess he's so quiet because there's nothing to see back there. he has nothing to talk about. he sounds pretty bored."
Way to take a compliment and turn it COMPLETELY around. Yeah! He's good in the car, therefore I'm making a mistake by RFing him!