From OMIM
Benign familial neonatal seizures is an autosomal dominant disorder characterized by clusters of seizures occurring in the first days of life. Most patients have spontaneous remission by 12 months of age. The disorder is distinguished from benign familial infantile seizures (BFIS1; 601764) by an earlier age at onset. Deprez et al. (2009) provided a review of the genetics of epilepsy syndromes starting in the first year of life, and included a diagnostic algorithm. Genetic Heterogeneity of Benign Familial Neonatal Seizures See also BFNS2 (121201), which is caused by mutation in the KCNQ3 gene (602232) on chromosome 8q24, and BFNS3 (608217), which has been associated with a pericentric inversion on chromosome 5. See 269720 for a possible autosomal recessive form.  http://www.omim.org/entry/121200

From MedlinePlus Genetics
Typically, seizures are the only symptom of BFNS, and most people with this condition develop normally. However, some affected individuals develop intellectual disability that becomes noticeable in early childhood. A small percentage of people with BFNS also have a condition called myokymia, which is an involuntary rippling movement of the muscles. In addition, in about 15 percent of people with BFNS, recurrent seizures (epilepsy) will come back later in life after the seizures associated with BFNS have gone away. The age that epilepsy begins is variable.

A test called an electroencephalogram (EEG) is used to measure the electrical activity of the brain. Abnormalities on an EEG test, measured during no seizure activity, can indicate a risk for seizures. However, infants with BFNS usually have normal EEG readings. In some affected individuals, the EEG shows a specific abnormality called the theta pointu alternant pattern. By age 2, most affected individuals who had EEG abnormalities have a normal EEG reading.

Benign familial neonatal seizures (BFNS) is a condition characterized by recurrent seizures in newborn babies. The seizures begin around day 3 of life and usually go away within 1 to 4 months. The seizures can involve only one side of the brain (focal seizures) or both sides (generalized seizures). This condition is often associated with generalized tonic-clonic seizures (also known as grand mal seizures). This type of seizure involves both sides of the brain and affects the entire body, causing a combination of seizure types: tonic seizures, which are characterized by uncontrolled muscle stiffness and rigidity, and clonic seizures, which are characterized by uncontrolled jerking of the muscles. Seizure episodes in infants with BFNS typically begin with tonic stiffness and pauses in breathing (apnea) followed by clonic jerking.   https://medlineplus.gov/genetics/condition/benign-familial-neonatal-seizures