Originally Posted by
Trakhak
If that's a current photo of your granddaughter, she might be able to get a few more months out of that 20" bike. In any event, you're undoubtedly going to make sure that she's comfortable with the greater reach to the brakes and the overall size of the 24" bike before taking her out on extended rides.
That's from last year on her 1st ride with the VOOM 4. (hence the "last spring" caption) I've since raised the seat about 3" and she can still put her feet on the ground from the seat.