My little boy didn't start sleeping through until he was 2 months old, so that's brilliant that your little girl has started sleeping through already 😊
My LG was the same..but then sleep regressions came at 4 months and then at 6 months and she was waking up every 2-3 hours for months..I was really glad I as not waking her up when she was sleeping at 1/2 months old. Just monitor her weight that she is gaining as much as she should.
As long she is gaining weight and is having enough wet nappies I wouldn't bother waking her up. If you're worried you could try to feed her while she sleeps. Newborns are normally very good at drinking and sleeping at the same time 😁
My LO is a little over 4 weeks and sleeps a good stretch as well. From my understanding, If they are over birth weight and are eating and gaining well, they can sleep as long as they want. I do still wake her up at least once in the middle of the night just in case. Mine eats at least 6-7 times during the day and is bottle fed with breast milk. We are going to the PED today so I am going to ask them as well!