True a rubber tire wheel

[Euphman06]

Got my 2 year old a 60's vintage kids bike. Back wheel wobbles like crazy when spinning though which is going to be hard for him to learn how to ride eventually with a wobbly tire to throw his balance. It has solid rubber tires so I don't know how to fix this problem. Any help?

 

[deorman]

Unless it has adjustable spokes, about the only suggestion I have is to lay it on the ground and step on it.