I'm afraid I have no record of Janet McDonald after the illegitimate birth.
Hi:
I came across this thread entirely by accident but I do have a little information.
Lachlan McBean of Knockando is my fifth great grandfather through his son Ludovick McBean. Lachlan McBean married Janet McAlaster on 18 February 1775 at Knockando. Janet McAlaster was baptized at Inveravon, daughter of Donald McAlaster and Isabel Black. Her baptism was on 11 June 1756. Lachlan and Janet had six children - Ludovick, Anne, Stephen, Elizabeth, William and Grace.
According to a testament dated 14 February 1785, Lachlan McBean died in February 1784 and Janet became his relict and executrix. However, the testament which took place a year after Lachlan's death, names her as Janet McDonald, indicating she had remarried, or at least taken someone's name - not surprising since she had six children all under ten. I can find no trace of the marriage or who the husband was.
I do know that Janet McDonald is buried in Spital cemetery in Aberdeen. She died on the 23rd September 1824. Her inscription reads "Janet McDonald widow of Lauchland McBain, a farmer of Knockando". Her age in the burial records is stated as 67, which fits with the baptismal record I have for her.
I do have copies of the burial records for Janet McDonald, the six children's baptisms, the marriage record of Lachlan McBean and Janet McAlaster, and the baptismal records of Janet McAlaster and her two sisters, Margaret (bap. 1761) and Isabel (bap. 1758).
Many of the McBeans are buried in Spital cemetery, including Lachlan and his son Ludovick and Ludovick's wife, Isabel Brymer.
Your information is interesting to me. I had no idea what happened to Janet in the intervening years before her death.
It is interesting that Janet is not buried on the McBean land in the cemetery, despite there being 35 people buried in the same spot, several of whom are mentioned on the headstone.
If there is anything else I can help you with, please contact me.
Adrian Powell (Canada)