The death notice of Maria Gertruida Loots lists her as a daughter of Gert Loots and Gertruida Loots born De Klerk. That couple can be identified as Gert Dirk Loots and Gertruida Frederika Christina Loots born de Klerk. This is consistent with the naming of her children: first a daughter Johanna (named after paternal grandmother), then a daughter Gertruida Fredrika Christina (named after maternal grandmother), then daughter Margaretha Jacoba (named after paternal stepgrandmother), then son Christian Jacobus (named after paternal grandfather), then son Gert Dirk Marthinus (named after maternal grandfather). Even the 7th son Gabriel Jacobus Hermanus Francois suggests a relation to Gert Dirk Loots, since his father was Gabriel Jacobus and his brothers names were Hermanus and Francois.
But biologically she can't have been a daughter, because Gert Dirk was born ca. 1803 and his wife Gertruida Fredrika Christina de Klerk was born ca. 1812. This couple having a daughter in 1821 is biologically not possible. Next to that, the death notices of Gert Dirk and his wife do not list a daughter Maria Gertruida. There is a a daughter Maria Catharina, but she was alive in 1896 and hence cannot be the same person as Maria Gertruida, who died in 1881.
Could it be that Maria Gertruida Loots was a foster daughter of Gert Dirk Loots and Gertruida Frederika Christina de Klerk?