My LO has decided she now hates the sleep sack after not using it during the summer. The two times I've put it on her for nap/bedtime have resulted in extended screaming and pulling at the sleep sack, when she normally doesn't fight sleep this bad.

How do I keep her warm without the sleep sack? She's 13 months. I don't really feel comfortable using blankets yet (and she also hates them... she doesn't like being under the blanket when we snuggle in the morning).