I know that most characters don't understand what Stewie says and only here his speech as baby talk but has anyone else noticed this weird thing where characters who can't understand him simply freeze when he talks near them? It's like the toys in the Toy Story universe when humans are nearby.
Here Stewie loudly sings the Mr. Belvedere theme song and Peter, Lois and Chris all stop and sit/stand in silence while Stewie is screaming the lyrics: https://youtu.be/hnuHjMUANTU
Here at around 4:24 minutes in Stewie has just been born and is talking to Brian as Lois holds him and Peter's right next to the bed: https://youtu.be/SMx93KgPCZ8
Sure they can't understand what Stewie says but they do understand Brian so while he's openly conversing with a newborn baby why don't they react to it? Later as they leave Chris asks if anyone else heard the baby and Lois dismisses it as ridiculous. So who does she think Brian was talking to literal inches away from her? Did she temporarily go deaf and somehow lose the ability to hear Brian talk?
On the episode where Brian gets a brain tumor removed at the end he's talking to Stewie as Meg is holding him sarcastically thanking Stewie for unilaterally deciding him being a bitter alcoholic who can only hang out with a baby is better than him being a happy idiot getting laid all of the time. Things nobody says to an infant who as far as almost everyone else knows can't talk or understand complex speech. Meg stood motionless and silent as Brian said it to Stewie not reacting at all.
This is a little nitpick that has always bothered me and my siblings but no one else seems to notice it.