Thank you for your query.
(seizures) sometimes are not related to how high the fever
gets, but how fast it goes up. If your child gets a mild fever, you should medicate her to avoid it to increase and have a chance of another seizure. In some cases, the pediatrician
has to prescribe an anti-convulsive medication to prevent new episodes. The good news is that most of the times the children stops having seizures as she grows older (four to five years-old).
About the calcium level, is she taking any supplements? Talk to your pediatrician about that.
If you want more information, go to this website, made by parents of children with febrile seizures: http://febrileseizures.org.uk/
Have a nice day and good luck.