Depends on when in May you are planning to travel, but last year we went to Italy - Lido de Jesolo (beach resort just outside Venice). It's a pretty short season here, that's why it would depend on when you are going, as the season only kicks off end of the month. But we loved it, so much so that we are planning a return trip this year with our 20 mth old. Flights with Aer Lingus or Ryanair, bus or taxi connection from airport only 40 mins, very family friendly resort with a long sandy beach, shallow gently sloping water, playgrounds every few hundred metres along the beach, lovely food etc. Great waterpark with plenty for young kids, also other play centres etc. We've been to Alcudia & Algarve few times before but feel that Lido de Jesolo meets our family friendly requirements and still allows us to have a lovely holiday in a resort that caters as much to locals as tourists. The main street is pedestrianised every night so families are out walking with children late at night, eating out together, no hassle anywhere, felt very safe there. Let me know if you want any further info.