refuah shleima. In regards to your observations, yahser koach for working in frontline. maybe you were fully protected when you did that, and now you are less careful? You can safely presume that you had it easier due to having a vaccine. If many months passed after the vaccine, presumably your antibody level went down but you still have B/T cells that will deal with the virus after you are infected.
If you and not the kids were the primary vector, your effect on them may have been low. So, I would suggest testing kids first for antibodies before deciding on vaccination. Maybe even if they tested positive on PCR, not sure about this.
Biggest logical error I see people doing is thinking that either vaccine or previous infection fully protects them and stopping all protections. If you are for a long time with an infected person, you will get a huge amount of virus load that will overwhelm your defenses.