My grandson was fine the entire day , he’s 2.5months old . We were out in the mall for five hours he was fine , until we came home and felt his body was warm , when we checked his temperature it was 202.6. Did not have his meal as he would normally have , had a warm bath , gave him Advil , milk thereafter which he refused and we did not force him he slept thereafter. We checked his temperature again it had gone down . What can be the reason for this happening? Pleaseadvise