Where are you flying from? Majorca is only around 2 - 3 hours from the UK and has some great options for a family like yours, and for trains the fantastic train from Palma to Soller is a must for a day out! Lots of all inclusive hotels and some good sized resorts that have very good hospitals / medical centres. If a hospital is really important then you will need to look at somewhere in the South like El Arenal, Santa Ponsa or Playa de Palma. (There is also Magaluf / Palma Nova but these are very lively and not recommended for families in the height of summer really) if you stick to these resorts then the coach transfer from the airport, or taxi ride is pretty quick and its also close to Palma for the train too.
Other choices would be Costa Brava in Northern Spain. Again some great AI hotels and a very good train service which takes you to nearby resorts and even to Barcelona too for a day out. Most of the bigger resorts have hospitals and some hotels will even have on-site or on-call doctors too.
These are the main issues: We need a family holiday for dh, me, my newly bereaved mum, and 2 sons who will be aged 11 and nearly 6 by then. Can't be too long a flight (mum) or maybe Eurostar? (Never been on it!) Can't be anywhere too out of the way as mum is nervous of being to remote in case of medical emergency (she has reason for this) I would love AI as I would quite like a break too! Activities for the kids, nice places to visit for adults. No idea what's best tbh... I would love a villa and pool somewhere but would also like a Break from cooking/cleaning etc I love Italy, Austria and Switzerland. We like trains! It's not going to be possible to keep everyone happy is it?