Visitation with children should be specified by court order. Some orders grant “reasonable visitation” while other orders may attach a visitation schedule to be followed.
“Reasonable visitation” is very ambiguous. If the custodial parent said “no” to 90% of the visitation requests, the judge might find that to be “unreasonable.” Otherwise, visitation is basically left to the whim of the custodial parent.
A fixed visitation schedule is preferable in that each parent and the child know exactly when and where visitation will occur. There is much less opportunity for conflict.