I would either put the daughter and lambs in the area you've made in the barn, or the mum with a buddy.
Apart from, as I understand it, colostrum is produced near lambing, so maybe still time to build up for her own lambs, natural colostrum has the 'local antibodies', so better than a packet.
I agree with others, I think you are going to give everyone more problems leaving them together at this stage.
But also as Sally says, you have to decide what suits you.
Sara, I see you are new on here, you will come to realise these people give the best on advice on sheep, they not beginners
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