My parents are buying my LO an early early birthday gift, which will be a 'big girl bike' (she has a tricycle) but I'm wondering what size is best. I know it starts at 12 inches and goes up. I was thinking 12 would be good for this summer but she will quickly outgrow it, I think?

What size bike did your LO start off with? How old/tall were they and did it last more than one year?