Some areas of Spain use preferently the diminutive suffix -ete (Dieguete), other areas use -ín (Dieguín)... The more general and usual suffix is -ito (Dieguito).
But keep in mind that in Spain the use of diminutives is not usual (and people neither are very fond of nicknames) and restricted to children; it is very infrequent to find an adult who goes by a diminutive (with some exceptions that can be more usual:
Pepita,
Lolita...). This is a huge difference between uses in Spain and in Spanish
America.
Lumia
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