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Presence of mucus in the stool is due to inflammation of intestinal mucosa. The common cause of inflammation is infection. Red raised blister
bumps around anus can also occur due to presence of bacteria in stools.
You can apply Siloderm ointment around anus after defecation. You should get stool of your 25 month old tested in a pathological Laboratory, and consult a pediatrician
with report for proper treatment.
Hope you found my response to your query informative and helpful.
With good wishes,
Dr.Chandra Shekhar Sharma