It is not wrong, but in the Claſſical period 'familia' had more the meaning of 'houſehold', and was often more about ſervants than kinfolk.
'Family' in our typical modern ſense is rather difficult to expreſs in Latin.
This has come up ſeveral times before, and you really ſhould ſearch our old threads.
Yeh i have searched alot came across alot of diffrent things but most of them came out as it ain't wrong so i guess it aint BUT if one of you can give me a better tranlation that would be perfect he is getting his tat tomorrow silly boy..
Familia mihi omnia means "family (with the restriction AS said... see here for a complete definition of the word) is everything to me".
As other/more classical Latin translations I can propose mei ante omnia = my family before everything; meos ante omnia caros habeo = I hold my family dear before everything/dearer than everything. Ante meos nihil = before my family (comes) nothing.
Or if you don't want "my family" in particular but want the sentence to apply to everyone in general so just "family"; propinqui ante omnia/ante propinquos nihil, though it's perhaps less precise.