Jen,
There are many reason behind that cause her low milk supply. She must ensure she has done the following things:
1) resting enough
2) drinking enough
3) relax enough
4) massage enough
5) Lastly, latch on enough / on-demand
Rest enough to ensure milk production, drink enough especially hot drinks to ensure that there fluid in body to produce milk, relax enough to achieve let-down and massage enough to make sure that her milk ducts are not blocked.
On top of that, red dates and longan drinks can help in milk production, so ask her to drink more. I believe her milk production is not consider low, I guess that's the reason y some LC encourage latch on on demand for at least the 1st 6 weeks to ensure the milk supply and building up the supply, cos if u starts to pump too early, u will starts to feel sad, and wondering how come only so little milk. Every woman mentality will be like when pump must achieve a few ounces of milk, but true fact is we won't. Even when I TBF my no.2 till 6 months, I was like pumping only 3-4 oz each side. It took me 6 months to achieve that.
Another thing ur fren need to check is if bb is drinking enough. If she's drinking enough, bb should have 6-8 or more wet nappy in 24 hours and frequent, soft, watery poo. Check if she feels her breast soft after feeding and did she have any engorgement or any lumps around her breast that is obstructing the milk flow.
Some bb are lazy and they are not drinking enough or sucking hard to get the milk, hence the demand is not there already and eventually they fall asleep on the breast, aka sucking for comfort.
U must encourage her and tell her that she's doing well and ask her to follow the above and continues to breastfeed.... This is the passing stage and this is the place where ppl just give up on breastfeeding. If she really needs someone to talk to, she can always call the BMSG hotline at 63393558 to talk to those counsellor...
Hope the above helps