Visitation - Agreement Stipulation

In my current parenting agreement it stipulates I am responsible for transportation of the children for visitation.

Background: one child lives with me, the other 2 live with him. I live in Arizona, they live in Wilmington, NC.

My ex-husband believes this constitutes as me having the obligation to provide transportation from the Raleigh airport to Wilmington. My youngest daughter is 7; the airlines do not allow children under the age of 8 to fly on connecting flights. To this, it is only possible to get her as far as Raleigh. In the past I have accommodated by having my immediate family make the journey, but this is growing old for them, and they have other obligations in their lives besides accommodating my ex-husband. He has never show appreciation to them, and in fact has entered (un invited) my elderly grandmother’s home at 2am demanding his children after a late arrival from the airport.

He refuses to pick her up for an upcoming visit~ Is it reasonable that a judge would expect him to make the effort to pick up his children from the airport if I reimbursed for ground transportation at a reasonable rate?