From:
https://www.canada.ca/en/immigration-refugees-citizenship/services/immigrate-canada/family-sponsorship/other-relatives/who-you-can-sponsor.html
Option 2: other relative
You may sponsor
one relative, related by blood or adoption, of any age if you meet
all of the conditions, including:
- you don't have a living relative you could sponsor instead, such as a:
- spouse
- common-law partner
- conjugal partner
- son or daughter
- parent
- grandparent
- brother or sister
- uncle or aunt
- nephew or niece
- you don’t have any of the above-named relatives who is:
- a Canadian citizen
- a permanent resident
- registered Indian under the Indian Act
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In order to sponsor one sibling (not multiple as that's not possible), the sponsor must not have any relatives in Canada who are Canadian citizens, permanent residents or registered Indians and the sponsor must also not have a spouse, common law or conjugal partner, children, parents or grandparents alive somewhere in the world as they would take priority sponsorship wise.
If all of these conditions are satisfied, then the sponsor could sponsor one sibling under the lonely Canadian rule.
Otherwise, the sibling(s) must find a way to immigrate on their own.