Got diagnosis with hpv, had cone biopsy 4 yrs ago and normal pap since. Do I still have hpv? Can it still affect me, my hubby and child?

MAYBE. The cone biopsy got rid of the abnormality on the pap smear. There is a percentage of people where the hpv clears, but in others it is still present though not affecting your pap smear it might cause problems in you, but raelly should have no effect on your child.
Can be retested. Hpv is equally likely to do any of 3 things: go away, stay the same, or get worse (warts or cancer). A cone biopsy removes most of the hpv from your body, but you should continue to have follow-up to make sure. Testing (or retesting) can be done with a swab to check for high-risk types of hpv. You are not contageous to your children, but there is now a vaccine available for both boys and girls.
Maybe. HPV is a family of viruses well known to persist in the tissues forever in some patients. A cone can remove those located in the affected area, but is no guarantee that there may be some lingering nearby. Some people shed virus intermittently & can transfer the germ. Your kid is at no risk. You face a lifetime of periodic pap smears to be sure it does not return.