Yes, it REALLY is possible to sponsor a spouse while you're abroad, but it isn't REALLY easy. You will be required to successfully demonstrate that you will resettle in Canada with him. It seems, from what I've read, that the evidence that is required of you depends entirely on the discretion of the IO processing the file at the overseas visa office. So have a strong case in that regard - and put your best foot forward when you submit the application to avoid delays in processing.
Whether or not your husband can accompany you to Canada prior to approval of his PR visa depends on whether he is visa-exempt or not. Your member name would indicate that maybe your husband is from Thailand, and because citizens of Thailand are required to obtain a visitor visa before they can board transport to Canada, it is not likely he would be able to accompany you to Canada prior to being approved for permanent status. That's because, in order to get a visitor visa, he needs to demonstrate that he has significant ties to Thailand, and that he would return there at the end of his authorized stay in Canada. Having a wife and child who are Canadian citizens is not going to help him convince a Canadian immigration officer that he won't want to stay in Canada permanently - and, in fact, having filed an application for Permanent Residence pretty much confirms that. Because the IO has no way of knowing whether a PR visa will actually be approved and issued, s/he must deny the request for temporary status.
Wanting to minimize the amount of time you have to be separated is entirely understandable so, assuming you're a Canadian citizen and authorized to do so, you're probably better off staying with him in Thailand while you apply to sponsor him. You should include evidence that you have made arrangements for housing, employment or school (for you), and that you are severing ties to Thailand in preparation for your return to Canada. You can also submit letters of support from family and friends in Canada who are willing to testify that they can provide the necessary accomodations and funds for you and your family once you get back to Canada, until you are settled. Immigration Canada wants to be sure that new immigrants will not have to apply for social assistance once they arrive in the country.
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