Travelling with our three yo was the one thing I was least looking forward to but my worries soon disappeared. She was great on the flight (Virgin) and loved having the swimming pool at the Villa. Food wise, there's everything you need from Chicken & Chips to Fois Gras and Lobster. The best beach for the family by far was Pigeon Point. Certainly worth the £5 per day for a family of four. The locals really took a shine to her and all restaurants, even the great eateries such as The Seahorse Inn (highly recommended) and Coco Reef Hotel (not so great ) welcomed families. Pizza Buoys served up a "Dominos" quality pizza which kept the girls happy on those "just get them fed and into bed nights
The Caribbean sea was calm enough for her to confidently float with her arm bands on. The local pharmacy had an equivalent to Calpol which was useful. The supermarket (penny savers) had everything needed from Frosties to mosquito repellent. The temps were just perfect and with SPF 50 the girls played all day in the sun. We put the air con on before bed and then just ceiling fans for the rest of the night as it got too cold, definetly pack some nighties / pijamas for the little'ns.
After travelling all around the island we found the best beaches were all around the Crown Point area. Speyside, although listed as a swim beach is certainly not. Also, always fill up your car at the main petrol station in Bon Accord as the others around the island have either closed or have run out of fuel
Recommendations to eat (all quite expensive but that's just the way it is in Tobago.
Breakfast: House of Pancakes, great service and excellent Pancakes.
Dinner: Bamboo Mile (on the road but good food and Service), The Seahorse Inn (Best by far, Reef and Beef please), La Tartaruga ( excellent food, service and the wine list is world class)
Beaches: Pigeon Point, Stone Haven, Canoe Bay. around 4pm the fisherman offer their catch for sale near Stone Haven and Pigeon Point which is great for a night in and BBQ.
Have a great time !
In summary, a great place to take the kids, a bit limited for good beaches, safe and welcoming.