B.
Technically she is sleeping through the night, "through the night" according to peds is 5-6 hrs strait. it doesn't mean sleeping on your schedule. Putting an infant on a schedule is over rated, feed on demand and put her to bed when she looks tired. What's wrong with letting her sleep when she falls asleep? Isn't that what you do? sleep when you fall asleep? She needs as much sleep as she can get to grow, and remember her tummy is only as big as her little fist so she's gonna need to eat in the middle of the night. Don't let her CIO she's too young. Most babies don't sleep through the night at 4 months old. the average age is 13 months. I have one that slept through at 12 months and one that didnt sleep through until 3 years almost. and I didnt do anything different with either of them, Kids will sttn when the are ready. pick up " no cry sleep solution" by elizabeth pantley. and my second advice is put that 3 yr old back in bed and get a gate so he can't come into your bed, that's whats making you tired not the baby getting up once at night. You can't get good sleep with little feet sticking in your back or legs or elbows in your face or stomach. BTDT, put the big boy in his bed and make him stay there. Just keep taking him back to bed when he gets up. he will eventually get the point.
do NOT follow baby wise it is the ped association recommends against this book, many babies that have been put on this system end up with a failure to thrive from their ped. They litteraly starve their babies.
In the April 1998 issue of AAP News, the official publication of the American Academy of Pediatrics, pediatrician Matthew Aney, M.D. says "On Becoming Babywise has raised concern among pediatricians because it outlines an infant feeding program that has been associated with failure to thrive (FTT), poor weight gain, dehydration, breast milk supply failure, and involuntary early weaning...the book makes numerous medical statements without references or research, despite that many are the antitheses of well-known medical research findings...many parents are unaware of problems because the book is marketed as medically supported."
http://www.rickross.com/reference/gfi/gfi1.html
here is a story from a mom that actually used babywise.
http://www.thecrashpad.com/blogs/index.php/2005/04/27/on_...