Just capitalize the firs word Ann. This part of the letter is often refered to as "the complimentary closing".
The complimentary closing (omitted in the simplified letter format) appears two lines below the last line of text. Its alignment varies with the format of the letter:
In block letters, the complimentary closing
appears flush with the left margin.
In modified and semi block letters, the
complimentary appears right of center or may
be flush with the right margin.
Complimentary closings for business letters include:
Sincerely, Sincerely yours, Thank you,
Complimentary closings for informal letters include:
Best wishes, Kindest regards, Regards,
Best regards, Cordially,
Complimentary closings for very formal letters (those addressed to dignitaries and high officials) include:
Yours sincerely, Respectfully yours, Respectfully, ;-)