No, the sponsors in the context of sponsorship of a dependent child do not have to be resident in Canada. So they can do the sponsorship, the processing can take place, and in fact these cases are expedited.
In the rare event that an individual may be stateless, as I indicated in answer to Mr. Telegdi's question, there are other kinds of travel documents that can be issued. There's something called a certificate of identity, for example, that can be issued to these individuals. Likewise, the International Committee of the Red Cross has a travel document that can be issued for stateless persons. Either of these kinds of documents can be used for the individuals to return to Canada, and those documents are certainly recognized by Canada to permit them to come back to Canada.