USA Today has a good write up on her that should fill in a lot of the missing biography. She was born at 5:42 PM Yellowknife time why her Ascendant is in the second house of Taurus — as this is how the Morinus house system adjusts for the northern lattitudes (see Mrs Fred Trump, the mother of President Donald J. Trump, sr. for another example) and highlights her natural gifts that will help in creating her financial affiars.
Ms. Kidder’s mother was Canadian but her father an American from New Mexico.He was a dynamite expert and the family often travelled to remote locations for his work. Unlike Senator Cruz, born to an American mother in Alberta, she was not automatically granted US citizenship, as she did not receive it until 1989. Frankly, we do not understand the disparity unless some law changed at that time.
She lived in Livingston, Montana, not far from her first husband Thos. McGuane the writer and father of her daughter, Maggie. There is no mention of where the daughter and family resides in any of the news articles.
It’s a Choo Choo!
Ms. Kidder’s chart is a Locomotive because of its three legs from the required Grand Trine and one opposition from the Aries Moon to Libra Sun at 24.33, It is a bit woobly though, because one of the legs, Saturn in Virgo at 03.7 is out of quadrature — the other two legs are in fire (Sagittarius and Aries.) This puts a lot of emphasis on that Saturnian leg, making her fiery spirit a bit more headstrong, proud and capricious than it would been naturally if that have been Sagittarius, but it may also explain why all three of her marriages were short lived: she was easy to like but hard to live with. Since this aspect is in the fifth house of offspring, and conjunct Venus, an easy substitute for her daughter, this would have given the two women lots of personality clashes as the younger women would have been just as sensitive to real or perceived slights as she.
Her Venus at 13.12 in her sixth house with the Sabian Symbol of “through a seemingly inaccesible mountainous country the telephone linemen carry out their work” would also show how much good looks helped her in career as well as Neptune at Libra 13.10 “the courtyard of Spanish hacienda in a tropical country is revealed” as both highlight her ability to connect with people and self-faith in getting the job done.

While strong in the earth triplicity, Margot is weak in the water element. This makes her oversensitive and very sympathetic. In reverse, this also made people very sympathetic to her, as they sensed her fragility and vulnerability.
Her South-west wing is totally devoid of planets encouraging her self-sacrificing nature yet there is a strong desire for publicity and personal acknowledgement, probably why she chose Mother’s Day, so that her daughter would remember her, for her demise.
Her Ascendant at 28.38 Taurus in the second house, as previously noted, is opposite her Mars in Sagittarius and also out of quadrature, giving Kidder a fiery and stubborn temper. This symbol of “two garrulous old cobblers are working side by side” highlights the inner battle Kidder faced from her bipolar mental disorder that so disrupted her life until she found help in orthomolecular medicine (vitamin supplementation pioneered by Dr. Linus Pauling.)
The point focus is at Saturn, that earth leg, and overemphasizing her self-reliance and endurance in making her career success and in just getting through life in general — her maniac episode when she cut off her hair (an outward skeleton of herself so that she would not be found) would be a great example of how this worked in her life.
The time chosen for death is about when her daughter showed up at the morgue to identify the body from Maggie’s husband’s report to People magazine. As for Superman, it t would seem now that only Gene Hackman (age 88) survives from the movie. Here’s a small clip. Catch the whole thing when you can.
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Updated: August 10 2018 – Friday
As we politely put it, Ms. Kidder chose her day and her death has been officially called a “suicide” as she died of
a result of a self-inflicted drug and alcohol overdose,” Park County coroner Richard Wood said in a statement Wednesday. No other details were released.
This is supported by transiting Jupiter in her eighth house conjunct her native Ceres, an asteroid that suggests mother and child relationships that is also conjunct in Scorpio Chiron in her natal chart, suggesting that this bond was rather fractured because of Margot’s mental illness and strong career drive (square Ceres in Leo on the fifth house cusp). We hope that her daughter finds peace through this tragedy.