Our twins are 15w2d old do we've just gone from 2 to 4 (the oldest being 4.5yrs) personally I think the biggest transitions are firstly going from no children to one but then for me the biggest change was going from 1 to 2 children and learning how to handle multiple children, afte rthe second i think its just more of the same (handling multiple children) I think go for it, your capacity grows as your family does!