I always find Myer have them - I too get 100% cotton cos both my kids have had eczema from a young age for the first year so I have to be careful with clothes too - people think I am just fussy when they give us pressies for bubs and I check the tags to see what they are made of
I got a heap on sale at Myer ages ago, plus the ones I have gotten from Kmart - Mother's Choice or something like that they were, they were all 100% cotton too. The Target ones are 100% cotton but they are so thin and crappy they aren't worth carting home.
Target has 100% cotton sheets - they didn't look too thin and nasty to me. I've also seen them at Big W, but as we'd already bought a few sets from Target I didn't bother checking the quality.
I've seen a few different brands in baby shops - but they seem hideously expensive in comparison!
We're the same - neither DH nor I can cope with sheets that aren't 100% cotton (it feels like sleeping in a plastic bag!) so there's no way we're going to make our little one even try it!
For my first baby 13 years ago (!) We were struggling for $ but I wouldn't compromise on 100% cotton so I went to an Op Shop and bought some great sheets that felt like ex-motel sheets.... very thick, you could tell it was 100% cotton, probably 700+ thread count too (I love my 1000 count sheets these days!) and my mum made them up into cot sheets. I soaked them in Nappy San first. So that was dealt with for about $10 from memory. Got about 4 sets and that was enough... people bought us a few extras and we were given a few extras... but the Op Shop ones were the nicest. They fitted perfectly too because mum was able to measure the mattress.
I agree with BW too.... sleeping in synthetic feels so humid and yuk... just like a sleeping bag.
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