The Canada Child Benefit replaced
the universal child care benefit (UCCB) and the Canada child tax benefit
(CCTB). UCCB was discontinued as of July 1, 2016, so except in rare cases, most
people would not have gotten a RC62 slip in 2017.
FYI If you got UCCB, then it is taxable. If you got the new CCTB, it is not taxable.
More information on the Canada
Child Benefit: https://turbotax.community.intuit.ca/replies/2648036