This is a bit of a grey area because accommodation requests are handled on a case-by-case basis.
Employers do have the right to request information as long as it pertains to the accommodation request. This may include documentation (e-mails and correspondence) to and from care providers or specialized facilities. If the accommodation requested relates to the medical needs of an employee’s family member, the accommodating manager (usually HR) may request objective medical information related to the employee’s request to substantiate/explore accommodation. This confidential medical information should be provided only to the person in charge of accommodations and should not be given to other management or staff. The accommodations manager can liaise with medical practictioners, verify medical information and if possible assist with options and referrals. Taken from City of Toronto’s “Guidelines for Accommodating Family Status“
An accommodation will be considered appropriate if it will result in equal opportunity to attain the same level of performance or to enjoy the same level of benefits and privileges experienced by others, or it if is proposed or adopted for the purpose of achieving opportunity and meets the individual’s needs related to family status. Taken from Ontario Human Rights Commission’s ” Policy and Guidelines on Discrimination Because of Family Status. Sec VI The Duty to Accommodate“