Dn(iece) was born 12 days early just after Christmas weighing 6lb 6oz (second baby, dn1 was 8lb and fulll-term). Since then she has lost weight almost every day (now 10 days old) other than the 2 days where she and d-sil were readmitted to hospital for monitoring. She is being breast-fed, waking to feed and appears to be latching on & sucking well. Whilst in hospital they carried out a whole range of tests and have excluded anything obviously wrong (malabsorption etc) but are concerned that at home she loses weight and that her poo is bright green (not new baby olivey green, it really is lime!). Any thoughts on what may be wrong (d-sil is v pro bf and fed dn1 until she was 13 months)?