I heard they are supposed to eat 5oz's by now. What this mom needs to do is this, take a Ziploc bag, place 3 ounces in it, hold it up against the baby's body and see how large 3 ounces is. If she's 3 weeks old, I'd really need to know how much she weighed, but you can't over expand a baby's tummy. I have a feeling she's not going back to sleep, and I don't know where she got the babies take 5 ounces at 8 weeks. We're different individuals.
Some babies think they've got hollow legs.
Until a stomach has the capacity to hold more then she's not going to sleep much longer. The first thing you do is take it away in the day, then transition into the night. If he's having 3 naps a day, take it away the last nap of the day, then second to last, then all 3 naps. The other thing is just take it away and have some fussy periods where you have to go in in the night and calm him down. It's a prop, that's why I don't like pacifiers after 3 months, after that it's a prop, not a pacifier.