Your text content controls are of the rich text kind. If you change them to the plain text kind, you can go to the next one by using the tab key.

Personally, too, I'd be inclined to use:
• dropdown content controls with M/F options for 'Sex';
• dropdown content controls with Single (Never Married)/Married/Defacto/Divorced/Widowed options for 'Marital';
• date content controls for the birthdates; and
• dropdown content controls with the appropriate options for 'School', 'Physical Cond' & 'Relation' and, perhaps 'Employer' (depending on what you want there).
Doing so will both expedite the forms completion and ensure consistency of responses.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]