This answer is based on several clarifying comments that have been posted on the question. However, the answer still remains speculative since we cannot know the actual expression that was used by your grandmother.
The substantive that starts with [v] and means (little) woman or wife could be:
- dat Wicht (German: das Mädchen; English: the girl),
- dat Wiev (German: das Weib, English, literally: the wife, more likely the woman),
- or the diminutive dat Wievke (German: das Weibchen, English: the female, in archaic words: the wifie or the little wife/woman).
By way of comparison, the usual translation of woman or wife would be de Froo (German: die Frau).
Considering that the pronunciation of the concerned word is described as “veefuh”, “vifa”, or “veefa” (with two syllables), the diminutive Wievke seems to be the likely candidate.
This word also appears in other cute expressions such as dat Seewievke (English: the mermaid) and dat nakend(e) Wievke or dat witt(e) Wievke (English: the snowdrop [flower]).
The adjective that starts with [l] and that sounds roughly similar to the above-mentioned substantive (also with two syllables) could be:
- lüttjet (German: klein; English: little), e.g. lüttje Wicht (English: little girl), or
- leev (German: lieb; English: kind, nice, sweet, good, likeable, lovable, or dear [the word is related to English love]), e.g. leve Wievke (English: dear (little) woman).
(Note that the neuter singular adjective ending is sometimes omitted; e.g. lütt Wicht.)
The sought-after expression should mean little wifie; however, the considered diminutive Wievke already implies the attribute little. Therefore, the adjective does not necessarily have to mean little and could mean something else. Since the pronunciation of the concerned word is described as “leaveuh”, “liva ”, or “levah”, the adjective leve seems to be a more likely candidate.
Thus, the complete expression, which is described as “leaveuh veefuh”, “liva vifa”, or “levah veefa”, would be leve Wievke [ˈleːfə ˈviːfkə].
(By the way, in East Frisian Low German, the letter v should be pronounced [f] rather than [v]. Hence, the locals are unhappy about the pronunciation of Jever in German beer commercials.)