I have a dozen close relatives, all with 4+ jabs and no problems with anyone. All are doing well and 3 of us actually got infected with symptoms and tested positive but recovered in just a few hours without any need for medications or hospital.
I have two cousins that both had bad reactions to the covid vaccine.
My suspicion is that your genetics is what determines whether you have a bad reaction to it.
Close relatives would be expected to have similar genetics.