No, definitely not. The Resort won't have much flexibility with your room option at that point since it's a timeshare resort. While they can often move your room within the same room type, they don't really have the flexibility to move you into a different room category.
Your 2 best options would be either downgrading into a 1bdrm Deluxe unit (to gain the sofa-bed), Or you could bump up to a 2bdrm (deluxe may actually be cheaper to rent than the 1bdrm presidential since the point cost is the same, but commercial renters can often utilize discounts and other tricks to use less points for a 2bdrm deluxe vs a 1bdrm presidential).
One advantage of the 2bdrm unit, either deluxe or presidential, would be that not only would your granddaughter have her own room (Coolness factor for her... more privacy for you... and the ability put her to bed for the night and still stay up for some adult time without risking waking her since she's in her own room), but you'd also gain a 2nd bathroom which could help avoid some of the morning bathroom juggling that can happen from multiple people sharing a single bathroom on vacation.
