Complex sentence: At the moment, Romano and his wife have 4 children in total, however the show was created when they only had three so the show's children were based on Romano's real children (1 daughter and 2 twin boys).
Split into simpler sentences: At the moment, Romano and his wife have four children in total, however the show was created when they only had three children. The show's children were based on Romano's real children (1 daughter and 2 twin boys).