Three elements are essential in those two pictures. "The Cuckoo" and "Hide and Seek": the sun, the mother and the children. The sun is an old symbol of God, the mother is a symbol of the Nature-The Virgin Mary5) and the children are symbols of Mankind. In an earthly meaning you jusst see a mother who is playing with her children.
5) In Russia motherhood is a central motif in religion: "The Holy Mother of God, Mother Earth and the mother who gave birth to you with pain."