Cannot understand your issue. Serial numbers are numbers, not text like DOB?
If by 'headings' you mean column heading, then it is not a report heading (report has headers anyway, not headings).
Not being married is a marital status, so why is there no data for any person not married? Wouldn't the value be 'single'?
All that makes me wonder if your report is based on a crosstab query, and not an ordinary select query and not a table. That is the only reason I can think of that cause your report to not have a Marital Status field, which is what I think you are saying. In other words, it's not clear to me if the whole field is missing from your results some of the time, or if it's always there but sometimes there's no data.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.