Whitaker signed his 1989 Bowman card "Sweet-lou Whitaker" - not only signing the nickname "Sweet," but failing to capitalize his own given first name.
On a side note, I hated these '89 Bowman cards. They didn't fit in any binder sleeves and inevitably all ended up with dinged corners. Not a single "gem mint ten" '89 Bowman exists on the planet today. The only worse set in this regard is the 1989 Topps Big set. More on those at a later time.
Second Baseman, Detroit Tigers
1989 Bowman #103
Topps Fact: Acq: Via Draft
GMT Fact: The nickname "Sweet" was given to "lou" by the Tigers equipment manager in the spring training of Whitaker's rookie year after having washed his unmentionables. Mistakenly, "lou" took this as a term of endearment.