Feliz Aniversário, cebolinha. Eu amo muito você. Amor , pense em mim às vezes
Remarks about the translation
"buon " in portuguese is "bom", but here we know that the meaning is "feliz aniversário" in portuguese/ "happy birthday" in english.
an Italian would more often say Ti voglio bene - which translates literally as the rather tepid "I wish you well," but is usually more warmly intended. Ti voglio bene is also used of love among friends, including of the same sex