NO. Calcification of the placenta occurs in most pregnancies that reach term and can mean many things. It depends on how severe the calcification is, and at what gestation. Calcification in a 32 or 36 week pregnancy is abnormal. It occurs quite frequently in pregnancies that go beyond 42 weeks and can lead to poor perfusion and a low oxygen supply to the baby.
Brain damage, however, can cause seizures. If this baby experienced severe hypoxia during labor, permanent brain damage could occur, then the seizures could be a result of that. But, if the brain damage was this severe, you would see seizures before 6 months of age (usually right after birth) and this child would have many other problems in addition to the seizures.
A calcified placenta could mean that this baby was chronically stressed during pregnancy, wasn't receiving enough oxygen, and was a poor risk for a trial of labor. Was the child born vaginally or by C-section? Chances are that this baby had some fetal distress during labor, but a good OB team would have picked this up and delivered the baby by C-section.
The other thing to consider is: was this baby born prematurely? Severe prematurity can also result in multiple complications, including Cerebral Palsy, blindness, and seizures.
There are many causes for seizures in babies. If this is something new, then other causes need to be considered, like infection. Some small children will experience seizures with fevers.
http://www.emedicine.com/neuro/topic240.htm