We went for Charlotte's two-week appointment today. She gained 13 ounces in 7 days - she's now up to 6 lbs. 13 oz. The doctor said that it's fine to let her sleep until she wakes up during the night since she's gaining weight so well ... which is good because that's what I've been letting her do! She generally eats at 10 p.m., 3:30 a.m., and then 7 a.m. I consider myself very lucky to only be getting up once at night.
We are using a Miracle Blanket with Charlotte and it's awesome. I've never been able to swaddle a baby this well. We highly recommend it, since it's like a little straight-jacket!