It's hard to say how daycare affected Charlie's speech, because I'm sure he would've gotten much better at talking over time. But very quickly after starting daycare, Charlie's speech started to improve by leaps and bounds.
I've read that younger siblings start speaking sooner b/c they learn from their older siblings (better than from an adult). I guess for Charlie, there was a similar impact on his speech development from being around all those other talking toddlers.
Honestly, I was shocked and really grateful at the same time! I had thought that moving Charlie into daycare might slow down his development, but in fact in this respect at least it sped it up, Makes up a bit for him getting oral Herpes at daycare last month!
The other surprise was that he picked up all these words and phrases that we didn't teach him. Oh and songs: they sing songs there, so I will open up YouTube to a song and sometimes he will already know the words. (o_O)
Did your LO's speech improve after starting daycare?