If parents are separated and share custody, they can each claim the part of the childcare costs they actually paid. Receipts should be issued to both parents for their individual percentage paid by the childcare provider.
The following CRA information explains in greater detail circumstances of childcare and shared custody (Sec 1.34) and how to handle "reimbursements" between parents (Sec 1.35). https://www.canada.ca/en/revenue-agency/services/tax/technical-information/income-tax/income-tax-fol...
