What Causes Drainage Of Fluid Filled Sacs In Bowels Of An Infant?

My 18 month old daughter is healthy and behaving normal in herself but today I found several clear fluid filled sacs in her poo. They almost look like grapefruit segments only she hasn t had any citrus fruits lately. I m worried about this as I can t find any picture or explanation online that looks similar to what she had. My other chdren have had thread worms in previous years so I am fully aware about parasites. These don t look anything like. Please help !!