My child was born at 28 weeks, weighing 1kg He

Patient: My child was born at 28 weeks, weighing 1kg. He is now healthy 4 years old boy. We decided to vaccinate him for Meningitis B and he received Bexsero vaccine. I told the doctor tha he was born prem but she said that’s ok and nothing to worry. But i just read on Google that Bexsero has to be given with caution to premature children so now i am worried . Is there anything i should be aware of ? Will that cause him health problems ? This was his first dose but we need to get the second dose two months time

Doctor: