I loved the grobags. DS wore them until he came out of his cot at about 2.5 years. He could stand in them no problem. When it was really cold I'd put a blanket as well. I think they recommend you use them after buns is 6 weeks old. Not sure if this is still true. We had DS in a bassinet so no need for them then.
I have been getting all different sleeping bags, on eBay, and even got a Gro Bag from the op shop yesterday for $2.50.
Jim is a big kicker, he kicks blankets off.
The bags I've got range from a light weight - basically like a jumpsuit but with a bag instead of legs as someone has mentioned above; lightweight ones which would go over another suit, and the Gro Bag.
If you get on eBay, (this will create a problem for me lol but oh well) type in baby sleeping bag, check out those auctions which are about to end, and I've been picking them up for $1 with $6 postage. I think they are one of those things that are either useful for your bub or not.
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