The way I heard it on an album called "Bawdy Songs Go to College":

M is for the many times you made me
O is for the other times you tried
T is for those tawdry frat house weekends
H is for the hell that's in your eyes
E is for your everlasting passion
R is for the ruin you made of me

Put them all together, they spell M O T H E R
And that's just what I think I'm going to be.

Response:

F is for your friendly correspondence
A is for my answer to your note
T is for the tearful sad occasion
H is for your hope I'll be the goat
E is for the ease with which I made you
R is for the rube you think I'll be

Put them all together, they spell F A T H E R
And that's a rap you'll never pin on me.

(Pretty obnoxious song, n'est-ce pas?)