Well I managed to have a vacation last week with my 6-month old and husband. We stayed at a cottage near the beach in Ontario. And although I managed to avoid most work, I couldn't help but notice the lack of design at the cottage we rented. So here are some must-haves for your cottage design, or even questions to ask the owner when renting. 
1. Hose down area! If not for messy kids, then for your sandy feet. There's nothing like having an outdoor hose (perhaps run over your roof to collect solar heat, so it's not icy on your toes), with a rounded stone area for drainage to get all the dirt and sand off your feet and shoes before going in the house. 2. A clothes line. Especially if you are at a beach cottage. It should be located in the sun and quickly accessible in case of rain (especially during this summer). Nothing is worse than putting on a wet bathing suit, or one with an earwig in because it was damp over the porch railing! 3. A big deck. Hopefully located facing south so you can enjoy the sun. But see next must have... 4. Shade. Sun is great, but its hard to enjoy the outdoors if you and your children are burning up. Create overhangs , properly sized to reduce the hottest sun rays from 2-4. Or strategically plant some trees. No one wants to be cooped up inside the cottage on your vacation, because there is no shade. 5. Storage spaces. These can be for bikes, lawn chairs, strollers, firewood, etc, that don't fit inside the small confines of a cottage but are essential to keep dry for use at a moments notice. Overhangs, back sheds, or garages work great and should be convenient locations on the property, hopefully hidden from public view and unauthorized borrowers. 6. Natural ventilation possibilities. Whether your burning supper or its ridiculously too hot to sleep, most cottages do not have the luxury of AC, so the strategic location of operable windows with screens is critical. Natural ventilation cools the house, and doesn't allow the bugs in. Refer to number 4 to reduce the direct sun on the house and minimize indoor heating. 7. Windows towards the view. If you have a cottage site with a view, take advantage. Put big windows here, not small punched windows. Having a view when it rains on your vacation makes it that much bearable to be stuck inside. Too often I see houses with a great view and tiny little windows. It's a shame, really. 8. Soundproof walls, and not for the reasons your thinking! We vacationed with two other couples each with a baby under a year. So when baby one wakes up at 3am , it is a relief that baby two or three can't hear them and also wake up! Otherwise it makes for 6 very tired parents. 9. Protect your septic bed from vehicles. If your septic bed or tank is in a location where someone might park (ie your front yard). Make sure you prevent this. Septic beds are not designed to hold the weight of cars and can be damaged if parked on. Use plants, fences, or other landscape features to prevent accidental parking. Do not plant large trees close to your weeping bed either, as roots can also damage the system. 10. A roof and comfy mattress! It is a cottage, but if you sleep good, and don't get wet when it rains, it should be a good vacation! 
And one more bonus for good measure... 11. No carpets! Carpets hold beach sand very well, and who vacuums on vacation. Skip the carpet and go for easily sweepable floors. Lots of hooks around to hang coats, clothes, towels, etc. This should help keep clutter off the floor, couches, chairs, and tables.
1. Hose down area! If not for messy kids, then for your sandy feet. There's nothing like having an outdoor hose (perhaps run over your roof to collect solar heat, so it's not icy on your toes), with a rounded stone area for drainage to get all the dirt and sand off your feet and shoes before going in the house. 2. A clothes line. Especially if you are at a beach cottage. It should be located in the sun and quickly accessible in case of rain (especially during this summer). Nothing is worse than putting on a wet bathing suit, or one with an earwig in because it was damp over the porch railing! 3. A big deck. Hopefully located facing south so you can enjoy the sun. But see next must have... 4. Shade. Sun is great, but its hard to enjoy the outdoors if you and your children are burning up. Create overhangs , properly sized to reduce the hottest sun rays from 2-4. Or strategically plant some trees. No one wants to be cooped up inside the cottage on your vacation, because there is no shade. 5. Storage spaces. These can be for bikes, lawn chairs, strollers, firewood, etc, that don't fit inside the small confines of a cottage but are essential to keep dry for use at a moments notice. Overhangs, back sheds, or garages work great and should be convenient locations on the property, hopefully hidden from public view and unauthorized borrowers. 6. Natural ventilation possibilities. Whether your burning supper or its ridiculously too hot to sleep, most cottages do not have the luxury of AC, so the strategic location of operable windows with screens is critical. Natural ventilation cools the house, and doesn't allow the bugs in. Refer to number 4 to reduce the direct sun on the house and minimize indoor heating. 7. Windows towards the view. If you have a cottage site with a view, take advantage. Put big windows here, not small punched windows. Having a view when it rains on your vacation makes it that much bearable to be stuck inside. Too often I see houses with a great view and tiny little windows. It's a shame, really. 8. Soundproof walls, and not for the reasons your thinking! We vacationed with two other couples each with a baby under a year. So when baby one wakes up at 3am , it is a relief that baby two or three can't hear them and also wake up! Otherwise it makes for 6 very tired parents. 9. Protect your septic bed from vehicles. If your septic bed or tank is in a location where someone might park (ie your front yard). Make sure you prevent this. Septic beds are not designed to hold the weight of cars and can be damaged if parked on. Use plants, fences, or other landscape features to prevent accidental parking. Do not plant large trees close to your weeping bed either, as roots can also damage the system. 10. A roof and comfy mattress! It is a cottage, but if you sleep good, and don't get wet when it rains, it should be a good vacation! 
And one more bonus for good measure... 11. No carpets! Carpets hold beach sand very well, and who vacuums on vacation. Skip the carpet and go for easily sweepable floors. Lots of hooks around to hang coats, clothes, towels, etc. This should help keep clutter off the floor, couches, chairs, and tables.