
Quoting
Mr. Knowitall
It sounds like the order was drafted under the assumption that the parents would be living near each other (or that a form order was used without modification of boilerplate custody provisions), even though it would seem that whomever drafted the order should have known better. A right of first refusal is not going to be exercised if dad is living half-way across the country, nor is it likely to be exercised if dad is "only" 200 miles away.
Even if we presuppose that the custody court would sympathize with mom on the issue of visitation during the third and fourth weeks of extended visitation, it's not a basis to deny all summer parenting time.
Right of first refusal is about child care, not about time the children spend with relatives. It's also not a basis to deny summer visitation, even if mom "knows" that dad won't be at his parents' home.
Really, the parents should be working out a custody arrangement that is consistent with the distance between their homes, and the needs of the children, rather than engaging in a battle over language that doesn't even seem to have been appropriate at the time the order was entered.