Many leaders (past and present) have spoken about the fact we have a Heavenly mother. We dont know anything about her but I was thinking if we assume that Heavenly Father lives the higher law of Plural Marriage, does it mean that we then have more than one Heavenly Mother?
I think that we can safely conclude that our Heavenly Father has at least one plural wife--the mother of Jesus. Anything beyond that would be pure speculation. We can speculate about the length of gestation for spirits in the wombs of celestial mothers and multiple births, but nothing has been revealed about those matters. Mosiah Hancock had a vision wherein he claimed that he was shown that we were all born as sets of twins in the preexistence, male and female, but He was not President of the Church, and his "vision" is not official doctrine of the Church. Thus, we are left to speculate about whether or not we are all children of one Mother or many. It is all pure speculation. I don't know, and I don't have any opinion.