The only Rachel McKechnie showing on the 1901 census in Scotland, so happens with a Dumbartonshire birth place, is this entry - all the children showing as born in Helensburgh:
James Mckechnie 37, Jacktsman (?spl) b. Inchanan, Renfrewshire
Jane Mckechnie 36 b. Ireland
Andrew Mckechnie 14
John Mckechnie 12
Jennie Mckechnie 7
Amy A Mckechnie 5
Michael Mckechnie 3
Donald Mckechnie 2
Rachael Mckechnie 8 months
Address: 18 Clyde St E, Helensburgh, Dunbartonshire
Not sure if you are working back from an age at death in 1962.
Monica