An invitation letter is not a legal undertaking and it does not bind you, but it is read carefully. It has to name you, your status, your address, the dates, and what you are covering, and it has to be backed by your own documents.
Your full name, date of birth and address in Canada. Your status: citizen, permanent resident, or the permit you hold and its expiry. Your relationship to the applicant. The dates of the visit and where they will stay. What you are paying for. The number of people in your household.
Proof of your status, proof of your address, and where you are contributing financially, your bank statements, your notice of assessment or your employment letter. Some families also include a statutory declaration, which is not required but does no harm.
Close family in Canada is weighed against ties at home, so a strong invitation makes the ties reason more important rather than less. The application still needs the applicant's employment, dependants and property documented. Do not let the invitation carry the whole file.
Open the case, add your documents, share the link. Approvable drafts the invitation, and the readiness report tells both of you which side of the balance is still thin.
You can open the case, pay for it and add your own documents, then send the link to your relative so they can add theirs. One purchase covers the case whoever pays.
Our software reads your documents, checks every ground, tells you exactly what is thin and what would fix it, and writes the cover letter, the sponsor letter and the employer letter from the facts you gave. One re-run included within 30 days.