The hypothesis that bilingual persons think differently and even are different when using their various languages is an interesting, but also a difficult one to prove. Musing about my own German/Spanish bilingualism, it occurred to me that the word toddler might be of some relevance in this context. Perhaps it can shed some light on this subject. As the word describes something which seems clearly defined to me, I suppose it might give a meaning, a content, perhaps a boundary to a phase in life which for Spaniards and Germans, as far as I can tell by extrapolating from my own experience and recollection, is blurred away between the period in life when we are utterly helpless babies and my first memories of early childhood. My parents told me quite a few anecdotes about their troubles with me as a baby. God bless their patience! Then comes the time in my life when I start to remember things from my early childhood. But nobody has ever told me anything about the time between one and four years of age and I certainly do not remember anything about that time by myself. Why haven’t my parents told me anything about me at the age which the native Englishmen define as toddler? Perhaps because they do not see it as a separate phase in life, because it fades away in what for them was my “early childhood”, the more boring part of it, to be precise, when I could still neither read nor write, when my interaction with the world was rudimentary, when I was for them either a nuisance or plain boring, no longer a novelty (as in baby) and not yet interesting (as in child)? Perhaps some native English-speaking person can tell me if that impression is right, and if so, what his or her recollections of this time in their life are. What their parents told them about this time, and how it left a mark on their own self-recollection, if at all.
One way or another, what is clear is that neither German nor Spanish have a word for toddler. Kleinkind or niño pequeño are simply not clear enough. I think those languages (and many others) urgently need that word. So if I may be so bold, I would like to make a suggestion or two. For German, we might perhaps use the English word as it is: Toddler. It sounds Germanic enough to me. Or we might try to become a little descriptive: Stolperer, Stolperin. As for Spanish, I guess a good solution would be to use toddler in a Spanish way: todeler, todelera. Or perhaps it might be a better idea to change the word completely and say tropezón and tropezona. That is, if nobody comes up with something more appropriate.