My family (incl 3 kids 2yrs, 5yrs and 7yrs) just returned from a great couple of night's staying at Maria's Art Penthouse on Old Mint street, Valletta. You can't beat the location for exploring Valletta. I'd highly recommend staying actually in Valletta town rather than doing a day trip as the evening is much quieter, more chilled and really pleasant (after all the day trippers have left). The apartment is very cool, beautifully decorated, well equipped with everything you need, with cracking balconies and roof terrace. You feel like you have seen and stayed in real Valletta as this is one of the beautifully renovated original buildings. Sabrina met us, let us in, gave us wine, beer and milk and was very helpful and responsive throughout our stay. I think it highly likely we will be back.
One thing worth being aware of is that due to the nature of the original building the stairs in the aptmt are a bit treacherous for very young kids. But we all survived and I think the kids really appreciated staying somewhere a bit different to what they are used to. We all fitted in with plenty space - our 3 shared the 2nd big double bed but there is also a cot or sofa bed in the kitchen/lounge.
Thanks Maria and Sabrina!