They want letters from people who know your academic work. Normally, all three should be from teachers with maybe one max from someone you interned from. Usually the forms make this clear.

On the other hand, if you family is super, super prominent it will help. Super prominent means your dad is John Grisham, not your dad’s friend is John Grishman. Or your mom is heir to Microsoft. Something major. Its not, my Mom/Dad is the DeKalb county DA.

I don’t think the letter are likely to give you an edge. They could end up hurting you, since none are academic. I’d look at the applications for specifics and email both schools to ask about extra and non-academic letters of reccomendation.
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