Both are okay po actually 😊. Kasi need po masatisfy yung sucking reflex nya habang baby pa kasi pag nadelayed po yun or pinigilan, pag laki nya ibabalik nya yun para masatisfied yung mouth nya 😊. Katulad ng pagngatngat ng ballpen etc na pwede isubo 😊. This is according to Sigmund Freud Psychosexual Theory 😊😊