Question: What was the father of Vaiva the common Baltic god of?

Context paragraphs:
God in Mormonism: In orthodox Mormonism, the term God generally refers to the biblical God the Father, whom Mormons sometimes call Elohim, and the term Godhead refers to a council of three distinct divine persons consisting of God the Father, Jesus (his firstborn Son, whom Mormons sometimes call "Jehovah"), and the Holy Ghost (Holy Spirit).  Mormons believe that the Father, Son, and the Holy Ghost are three distinct beings, and that the Father and Jesus have perfected, glorified, physical bodies, while the Holy Ghost is a spirit without a physical body.  Mormons also believe that there are other gods and goddesses outside of the Godhead, such as a Heavenly Mother who is the wife of God the Father, and that faithful Mormons may attain godhood in the afterlife.

Baltic 21: Initiated by the Prime Ministers of the Baltic Sea countries in 1996, Baltic 21 is a regional expression of the global Agenda 21 adopted by the United Nations “Earth Summit.”  Being a network for cooperation, Baltic 21 links together stakeholders in a common endeavour for regional sustainable development.

Saulė: Saulė (Lithuanian: "Saulė" , Latvian: "Saule" ) is a solar goddess, the common Baltic solar deity in the Lithuanian and Latvian mythologies.  The noun "Saulė"/"Saule" in the Lithuanian and Latvian languages is also the conventional name for the Sun and originates from the Proto-Baltic name *"Sauliā" > *"Saulē".

Hindu–Islamic relations: Hinduism is a diversity-filled socio-religious way of life of the Hindu people of the Indian subcontinent, their diaspora, and some other regions which had Hindu influence in the ancient and medieval times.  In Hinduism God can be worshiped in the name one believes or in the form one believes and allows idol worship, hence Hinduism's concept of God does not contradict the concept of Allah, the Islamic God.  Islam is a monotheistic religion in which the supreme deity is Allah (Arabic: الله‎ ‎ "the God" : see God in Islam), the last Islamic prophet being Muhammad, whom Muslims believe delivered the Islamic scripture, the Qur'an.  Hinduism mostly shares common terms with the "dhārmic" religions, including Buddhism, Jainism and Sikhism.  Islam shares common terms with the Abrahamic religions–those religions claiming descent from Abraham–being, from oldest to youngest, Judaism, Christianity, Islam, and Baha'i Faith.

Balto-Slavic languages: The Balto-Slavic languages are a branch of the Indo-European family of languages.  It traditionally comprises the Baltic and Slavic languages.  Baltic and Slavic languages share several linguistic traits not found in any other Indo-European branch, which points to a period of common development.  Most Indo-Europeanists classify Baltic and Slavic languages into a single branch, even though some details of the nature of their relationship remain in dispute in some circles, usually due to political controversies.  Some linguists, however, have recently suggested that Balto-Slavic should be split into three equidistant groups: Eastern Baltic, Western Baltic (which is extinct) and Slavic.

Ktož jsú boží bojovníci: The song was sung with such intensity during the Hussite Wars, that it instilled fear throughout the enemy army, making it a weapon in itself.  One of the Imperial Crusades is believed to have fled the battlefield before the battle itself, just by hearing the Hussites singing proudly their hymn.  The hymn would be led by a Hussite priest, who would be carrying a ceremonial axe.  At the start of the 1433 war between the Polish and the Teutonic Knights of Prussia, the Hussites signed an alliance against the Germans in July 1433.  In the course of the war, they marched all the way to the Baltic sea at the town of Danzig.  The Prussian 19th-century historian, Heinrich von Treitschke, makes a clearly indignant reference to the Hussite taking of land near the Baltic Sea and to "Kdož jsou Boží bojovníci" with these words: "greeted the sea with a wild Czech song about God's warriors and filled their water bottles with brine in token that the Baltic once more obeyed the Slavs."

Perkūnas: Perkūnas (Lithuanian: "Perkūnas" , Latvian: "Pērkons" or "Pērkon", Old Prussian: "Perkūns", Yotvingian: "Parkuns") was the common Baltic god of thunder, one of the most important deities in the Baltic pantheon.  In both Lithuanian and Latvian mythology, he is documented as the god of thunder, rain, mountains, oak trees and the sky.

Hand of God (art): The Hand of God, or Manus Dei in Latin, also known as Dextera domini/dei, the "right hand of God", is a motif in Jewish and Christian art, especially of the Late Antique and Early Medieval periods, when depiction of Jehovah or God the Father as a full human figure was considered unacceptable.  The hand, sometimes including a portion of an arm, or ending about the wrist, is used to indicate the intervention in or approval of affairs on Earth by God, and sometimes as a subject in itself.  It is an artistic metaphor that is generally not intended to indicate that a hand was physically present or seen at any subject depicted.  The Hand is seen appearing from above in a fairly restricted number of narrative contexts, often in a blessing gesture (in Christian examples), but sometimes performing an action.  In later Christian works it tends to be replaced by a fully realized figure of God the Father, whose depiction had become acceptable in Western Christianity, although not in Eastern Orthodox or Jewish art.  Though the hand of God has traditionally been understood as a symbol for God's intervention or approval of human affairs, it is also possible that the hand of God reflects the anthropomorphic conceptions of the deity that may have persisted in late antiquity.

Vaiva: Vaiva is a Lithuanian female given name of Baltic origin.  It is a shortening of "vaivorykštė" (English rainbow).  A rainbow was considered one of the manifestations of the Pagan destiny goddess Laima.  Vaiva's father, according to Baltic mythology, is Perkūnas.  The name was popularised by V.Krėvė-Mickevičius tale "Perkūnas, Vaiva ir Straublys" written in 1922.

God the Father: God the Father is a title given to God in various religions, most prominently in Christianity.  In mainstream trinitarian Christianity, God the Father is regarded as the first person of the Trinity, followed by the second person God the Son (Jesus Christ) and the third person God the Holy Spirit.  Since the second century, Christian creeds included affirmation of belief in "God the Father (Almighty)", primarily as his capacity as "Father and creator of the universe".  Yet, in Christianity the concept of God as the father of Jesus Christ goes metaphysically further than the concept of God as the Creator and father of all people, as indicated in the Apostle's Creed where the expression of belief in the "Father almighty, creator of heaven and earth" is immediately, but separately followed by in "Jesus Christ, his only Son, our Lord", thus expressing both senses of fatherhood.

Supporting paragraphs: Vaiva Perkūnas
Answer: thunder