Firstly when booking, infant prices on Royal Caribbean vary and can be steep - suggest you negotiate if using an agent as we did.  We booked a travel cot which was very smart, clean and acceptable - no linen however so you may wish to bring asheet and baby sleepbag (I guess they woudl have provided linen if we'd requested it but we were using a baby sleepbag anyway.Embarkation took some time at Southampton and compared with other cruise lines wasn't as efficient - be prepared for a bit of a wait in the car and then again in line.We didn't book a balcony cabin as I was concerned about safety, we booked an outside cabin on a low deck and it was very good - good value for money and reasonable in size (as ship cabins go of course).  Bring a lightweight fold up pushchair if you can so it can go under the bed when not in use.  Other people left their larger pushchairs outside the doors of their cabins.  Actually now having seen the balcony cabins they are fine so I'd book one of these in future.The Windjammer is great with a toddler - usually easy to get a highchair and the staff are terrific - helpful, friendly and endlessly pateint and fun with the chidren.  We used it for breakfast, occassionally lunch and sometimes for dinner.  The pasta to order is especially good for children and there are plenty of sugar free dessert options too.  We found the formal dining room quite a challenge with a toddler - the staff were just as great but depending on how good your toddler is, it can be stressful.  We went to formal nights and a few others and stayed for as long Emily could reasonably manage.  There is a lot of glassware, cutlery etc. so it can be tricky.  If you have cruised with P&O as we have, we found that the food and service were nowhere near as good on Royal Caribbean. All the snack eateries were good and useful with a toddler - pizza, coffee shop and ice cream self serve on the pool deck.The rules about swimming pools are a real pain - you cannot take babies in nappies/diapers into the pools.  There is a tiny baby splash pool with barely an inch of water.  Good for play but not for swimming.  Only one adult per child in the splash pool which was also irritating when there are two parents and a child!The Fisher Price baby programme is outstanding - I cannot recommend it enough.  A parent does need to accompany the baby but we found it fun and Emily loved all the sessions.  There is a schedule of themed sessions - three a day and extra on sea days.  The staff were exceptional.  The toys were all in good condition, there were lots of them and every toy was sanitised at the end of each session.  The children were encouraged to share.There is a babysittign service for one year plus babies but we didn't use it.There are lots of details on the ship which are fun for children - the red dog on the balcony for example.  The ship is truly exceptional and vast.  The majority of places including the bars are child-friendly, there are a few which are adult only after 5pm which is perfectly reasonable.Overall, we found it worked well with a toddler and we wouldn't hesitate to do it again.