how would you write this sentence in predicate logic?

Question

All Mary’s relatives live in Boston, only her cousin John lives in New-York.

I'm confused about how should I translate the second part, whithout getting a contradiction.

Answer 1

For all x, if [ (x is a relative of Mary) and (x is not Mary's cousin John)] then x lives in Boston. AND Mary's cousin John lives in New York.

The "AND" here goes between the two, so overall it's a conjunction of two different predicate statements.

To make it look better one could invent predicates like $Rxy$ for x is a relative of y, and so on.