Brian Austin Green has called fatherhood an “amazing experience” after welcoming a new baby with his dancer girlfriend Sharna Burgess. The couple became parents to a son named Zane Walker Green on June 28 and he has now given an update on how the family is doing – insisting it has been an incredible few weeks for them all and he is thrilled by how well everything is going. He told E! News’ ‘Daily Pop’ show: “Zane’s amazing, Sharna’s amazing. It’s been an amazing experience, it really has.” Despite already being a step-mum to Brian’s kids from previous relationships, the actor admits Sharna fel…