Hi Barbara

I just checked the 1881 census for your james Rae and Jessie Ann Todd.
Dwelling: Tanglan Muir
Census Place:Methlick, Aberdeen, Scotland
Source: FHL Film 0203461 GRO Ref Volume 221 EnumDist 3 Page 8
James RAE M 54 M New Machar, Aberdeen, Scotland
Rel: Head
Occ: Wood Sawyer (Journeyman)
Jessie RAE M 53 F Methlick, Aberdeen, Scotland
Rel: Wife
Jessie RAE U 22 F Methlick, Aberdeen, Scotland
Rel: Daur
Occ: Serv (Domestic) Unemployed
Simon RAE 12 M Tarves, Aberdeen, Scotland
Rel: Son
Occ: Scholar
Margaret RAE 9 F Methlick, Aberdeen, Scotland
Rel: Daur
Occ: Scholar
James MURRAY 1 m M Methlick, Aberdeen, Scotland
Rel: Grand Son

Checked IGI for James Rae and Jessie Ann Todd children and found the following:
Jane Lawrence born 07 OCT 1864 in Methlick
Isabel Rae born 03 DEC 1853, chr. 20 DEC 1853 in Methlick
William 07 MAR 1856 in Methlick
Joseph born 18 NOV 1861 in Methlick

From the 1881 census:
Joseph is listed at Chapelton, Methlick, Aberdeen, Scotland
occ.:Farm Serv, unmarried

Well this info should at least help you with the birth years of her siblings.
I have a Margaret Rae b. 1787 Methlick? to James Rae and May Brown.
Margaret Married a John Ross. She died 28 Jun 1879.

Best regards
Karen Brettell