Give the family a week by the sea with just one change of hotel. Two Tivat nights make room for arrival beside the bay and a full day at a beach chosen for the children. Plavi Horizonti, on the Luštica side, is a separate trip from the central promenade. Four nights in Petrovac then leave three full days for the town beach, a Lučice cove visit and a possible Buljarica outing, with the same room waiting each evening.
Plan this as a June-to-September beach holiday. In July and August, swim in the cooler morning, take lunch and a shaded rest, then enjoy the promenade later in the day. Short visits to Tivat’s Buća-Luković estate or Petrovac’s Venetian harbour setting can add a sense of place between swims. A car or arranged rides make the beach choices flexible; a central Petrovac address also lets you spend whole days on foot. Choose the room by its actual approach to the shore, including steps and hills, and check the sea and current beach facilities locally. Day three is the only hotel move, and the last day stays available for the flight.