difficulty breathing; This is a spontaneous report received from contactable reporter(s) (Consumer or other non HCP) from medical information team. The reporter is the parent.  A 2-year-old male patient received BNT162b2 (BNT162B2), on 16Jul2022 at 11:00 as dose 2, single (Lot number: FT9142) at the age of 2 years, in left arm for covid-19 immunisation. The patient's relevant medical history included: "He has had the flu before" (unspecified if ongoing), notes: Know it is something viral. He has had the flu before, but it wasn't anything like this.; "he has an underlying condition, like asthma" (unspecified if ongoing), notes: Doctor is presuming that he has an underlying condition. There were no concomitant medications. Vaccination history included: BNT162b2 (Dose-1, LOT: FT9142, Expiry date:31Dec2022), administration date: 23Jun2022, when the patient was 2-year-old, for COVID-19 immunization, reaction(s): "Drug ineffective", "Doctor is presuming he had Covid when he got the second vaccine\ antigen Covid test was negative", "amoxicillin to prevent pneumonia", "respiratory distress", "being sick when he got the second vaccine", "runny yellow nose and cough they are assuming he has Covid because he is presenting the same way he did in Apr2022", "runny yellow nose and cough they are assuming he has Covid because he is presenting the same way he did in Apr2022", "Still wheezy and everything today", "occurrence of the difficulty breathing". The following information was reported: DYSPNOEA (medically significant) with onset 17Jul2022 at 01:30, outcome "recovering", described as "difficulty breathing". The event "difficulty breathing" required physician office visit. Therapeutic measures were taken as a result of dyspnoea.  Clinical course: This report was not related to a study or programme. The reporter (mother) was calling because her three year old son received second dose of COVID-19 vaccine on Sat 16Jul2022 and the following morning they had to take him to urgent care because he had difficulty breathing and they gave him a dose of Decadron. The child's doctor thought he had COVID, but it did not present itself until the next day. Verified the above information with the caller. Called to see if there was any data on whether or not her son should get the third vaccine in September. If him being sick when he got the second vaccine could possibly affect the building of the antibodies from this past dose on 16Jul2022. Difficulty breathing: Started about 1:30am on 17Jul2022. The reporter needed to take him to the hospital with breathing issues before. Back in Jun2022, he woke up in respiratory distress and they had to take him to the urgent care then as well. With this occurrence of the difficulty breathing, he was being treated with nebulizers of albuterol sulfate 4 times a day, amoxicillin to prevent pneumonia, 5 days of prednisone, Cetirizine HCL. Still wheezy and everything today, but better. Doctor was presuming that he had an underlying condition, like asthma that was contributing to all this. Doctor was presuming he had COVID when he got the second vaccine, the symptoms just hadn't presented yet. In Apr2022, he was PCR positive, but his antigen test was negative. This time, his antigen COVID test was negative, but they did not do a PCR. Based on the presentation of his symptoms, like his runny yellow nose and cough they are assuming he had Covid because he was presenting the same way he did in Apr2022. Know it was something viral. He had the flu before, but it was not anything like this. Does not think it was the vaccine. It was just bad timing when he got the vaccine. The doctor of the patient recommendation was that he get a booster again in Nov2022 after the third dose was Sep2022. Concern was that because he seems to be very susceptible based on being in the hospital in Apr and then this issue with the breathing. Hopefully, the vaccine will keep him out of the hospital. As of right now, this was the plan they will go for. If there was any other data or guidance feel free to reach out. She was calling to see if there are other recommendations for getting a booster early in these cases. Her son was not one of those kids that gets sick, coughs twice, and gets better. She wants to keep him as protected as possible.There were no additional Vaccines Administered on Same Date of the Pfizer. This event did not require a visit to Emergency Room. The patient went to urgent care on 17Jul2022. Has been to PCP three times and has a follow up scheduled for 3 weeks. The patient did not receive any other vaccines within four weeks prior to the vaccination. There were no adverse events prior vaccinations. Patient medical history including any illness at time of vaccination was none and other conditions were No. The family medical history were not provided. There were no relevant tests and investigations.