@Bootyyyy no this is normal
the developmental stages of humans in the early years of babies-toddlers-children that ages is around 0-5 has a lot of obvious mobility improvements that happen quickly.
Wolf Fur is a child [ i don't think he is a pre teen yet,or he is just starting in the adolescent years] so he'll stay about the same for a while
and of course a literal
baby which is almost nonverbal & almost completely un-mobile --to a
toddler that can start walk [barley]..to even a child is going to have a lot more noticeable differences then like...a pre-teen-teenager that will look about the same before they get a growth spurt.