I would just use a permanent marker. Write discreetly if using on clothes. It lasts but also scrubs off

Find a product that suits could be difficult I would use a reusable or throw away milk satchel and maybe just crossing off old date and time might be if use

I use disposable breastmilk bags and just use a permanent marker to write on them. And I’ve got labels from tiny me with my child’s name on them for the bottles. Then I just send the bags and empty bottles for them to sort out at daycare. I also have iron on labels from the same place for her clothing.

I used sticky labels for the breastmilk with a date and froze them. I use a laundry marker or pen to write their name on the label of their clothes.

At this time of the year you might also find some good deals for labels – worth a good online search.

Buy a set of sticky labels from tiny me or hippo blue – they are dishwasher safe and stay on for ages. I also write on bottles and containers in permanent marker. For clothes permanent marker and iron on labels

I love sew on tags as they stick and do not go anywhere! Labels, fabric or sticky can be purchased in bulk pretty cheaply and then you have them for years!

This is a really hard one, I would be interested in seeing people’s advice.

I was going to suggest engraving for tge bottles, but maybe wouldn’t suit you either. Permanent marker is another way, it usually scrubs off. But not sure you would want to do that each day either