Can you be the father of a child that was born august 31st and you had no contact from october29th to december 31st?

Yes, it is possible to be the father of a child born on August 31st even if you had no contact from October 29th to December 31st, as long as the conception occurred before the period of no contact. The key factor is the timing of conception, which typically happens around two weeks after the last menstrual period. If you had contact before October 29th that could have led to conception, you could still be the biological father.