We have been extremely happy with our mini kick that my petite DD (age 4.5) got at age 2 3/4 and was riding within minutes. I noticed on the website, you cn buy the 3 in 1 seat and add it to a mini kick so no worry about growing out of it. But I cant imagine a child over 18 months, especially one with an older sibling wanting to sit on a scooter. We took it on vacation last summer and our friend's 18 mos old DD scooted around on it without a problem.