Breastfeeding question!

Sarah

Hi there! I'm a ftm and I'm just curious how much breast milk a breast fed baby should be eating at 6 months old? My niece (formula fed) was eating 6oz bottles at 6 months so my family is convinced my daughter should be eating 6 oz. However, her father has been saying shes been puking a lot recently. Originally we thought it was from old donated breast milk, but it happened again today with breastmilk i had pumped last night! I'm not sure what could be causing it other than overfeeding. If you have another idea as to why, i would love to know! Thank you :)