We stopped using sleep sacks when the weather got warm because the temp in her room can fluctuate and get pretty warm. It's rarely below 73 in the summer, but usually it's warmer. In the winter it gets pretty chilly, though. Will it be worth it to start using a sleep sack again when she's gotten used to not having it? She will be about 18 months.

I have zero confidence in a blanket being of any use. She is a very active sleeper.