You dot have to wean just because you are returning to work (unless you really want to), she will be ok to not have bm while you are at work and she can have solids and water, if she is going to childcare her carers should be able to get her to sleep with out a feed. Babies figure out really quickly what they get out of each person who cares form them ie dad will give a cup of water and mum has boob and granny has songs and cuddles.. and it works for babies.
She can then just have BFs when you are home, it will save you from weaning before she is ready and will keep that comfort that bfing offers both of you.
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