They contain a lot of sorbitol, and a lot of fiber, and either of those can loosen stools.
My DD2 has the same problem with blueberries.
My approach has been to sharply limit quantity.
<--- me falling on my face after smelling a grape poo diaper.
SAHM to 6.5yo DS and 4yo DD. PCOS with two early m/cs. Married 8 yrs. Certified birth doula, writer, editor.
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Momma to Sweet Rosie 7/06, Lost Baby J 1/09 at 12 weeks pregnant, Spitfire Ada born 4/21/10, and Baby Boy due July/August 2013!
Aspiring urban homesteader, photographer, homeschooling momma! Blog link in my profile.