We went to Majorca several years on a row the last week in May 1st week in June and it did get a bit nippy on a night. However 2 years ago we went to mainland Spain at the end of July and last year for the middle 2 weeks in August and the kids never needed a cardigan/jacket at all & we were out some nights 'till after midnight.
The main difference we found was temp of sea/pool!
Take a jacket for on the plane as that can be quite cold sometimes and use one you could slip on for a colder night if needed.
Sun protection- my 3 had baby eczema and so i started with E45 sun cream but they were allergic to that so ended up with Boots own Soltan factor 50-fantastic stuff sprays on green so you know you've covered them all over and dries clear. Don't forget ears back of neck and top of feet.
Relax and have a fantastic time, a holiday is what you make it, believe me we have had some horrific times (that's a story for another day) but we always made the best of it. It is lovely just time for you, babe and hubby, no distractions like tv computer telephone and family etc.
Hope that helped good luck.
