The most important part of the immunological window period and the administration of the first foods is monitoring the child and his physiological reactions to the food being given. If, after the first taste of a new ingredient, such as a strawberry or tomato, it shows certain signs of intolerance, it does not necessarily mean anything. Redness of the mouth or rashes are the body's natural reaction to a new, previously unseen food component. Such reactions disappear within an hour or two. If a bad reaction to the same food appears again, it is better if you find a doctor who will advise you on how to proceed.\r