Hi ladies,
I'm coming to take advantage of your wide knowledge-base and advice

DS is 9.5 months and waking wanting to feed in the middle of the night. We're currently working on reducing the minutes.
My ped queried whether I supplemented b/f through ebm or formula as she wondered if the night-wakings were caused by a low supply during the day. However, as DS has never fussed in hunger, and voluntarily pops off the breast at each feeding, I always assumed he was satiated. In fact, his feeds have been getting shorter during the middle two of the day, and less satisfying for me, as he gets more and more distractible. So today, just for grins, I gave him 1oz of ebm in a sippy after our 3pm feed, which had been particularly truncated. He drank it all. I managed to squeeze out another 1oz this evening and offered it to him after his bedtime b/f. Again, he drank it all.
I really don't want to get started on the slippery slope of supplementing, as I feel that if I have supply issues in the first place, this will just compound them.
Any thoughts on what I can do? How can I tell if he's getting enough during the day? It sure does feel ridiculous to be asking this almost 10 months into the game, but like I said, he's never fussed in hunger. I thought about expressing perhaps 8oz worth and giving it to him -- once -- as his bedtime feed, just to see how much he would take. I could pump after he'd gone to bed for that night to minimise the effect on my supply.
Of course he's never taken a bottle, and is like a puppy in a water bowl with a sippy, but that's a whole nuther story

Any advice would be much appreciated.
TIA!
Katy