Thanks for your query.
at the time of teething
babies do get loose stools as they try to put everything,especially their hand into their mouth because of gum irritation.i advise you to give lactobaccilus sachet for 2 to 3 days,apply calamine
3 to 4 times over rashes and keep his bottom dry,you can also give rice water,coconut water to your baby.In case symptoms get aggravated take her to pediatrician
Your baby will be fine.