IMO
i think she would be ok with out it. My DD was born in th 90th%ile.. she is now 9.5kg at 25 months... we have had alot of issues.. mostly hers are absortion issues she will eat and eat..

our pead suggested polyjoule as well as high fat(cream and butter on everything)
how is she if she feeds herself? (no spoons) does she like to play with food?

the breast milk will be doing Alot of keeping her nurished(is she breastfed aswell as EBM?)

i hope it gets sorted soon.. at about your DDs age was when my DD started to "improve"