King Dasharatha, wives, sons worship God with clay idols

पुत्रार्थे पार्थिवीं मूर्तिं शैवीं दशरथो हि सः |

समानर्च विशेषेण वसिष्ठस्याज्ञया मुने || 31 ||
पुत्रेष्टिं च चकारासौ पार्थिवो भवभक्तिमान् |
ऋष्यशृङ्गमुनेराज्ञां संप्राप्य नृपसत्तमः || 32 ||

कौशल्या तत्प्रिया मूर्तिं पार्थिवीं शाङ्करी मुदा |

ऋष्यशृङ्गसमादिष्टा समानर्च सुताप्तये || 33 ||

सुमित्रा च शिवं प्रीत्या कैकेयी नृपवल्लभा |

पूजयामास सत्पुत्रप्राप्तये मुनिसत्तम || 34 ||

 

Sage (Narada), for the sake of obtaining a son/sons, that Dasharatha worshipped a clay idol of Lord Shiva, particularly because of the instruction of Sage Vasishtha.
Devotee of the clay idol of Lord Shiva, the best of the kings (Dasharatha) carried out a son-desire sacrifice instructed by sage Shringa in order to obtain (a son/sons).
His favourite Kaushalya, advised by sage Shringa, gladly worshipped the clay idol of Lord Shiva, for the sake of obtaining a son.
Best of the sages (Narada), Sumitra and Kaikeyi, dear to the king, worshipped Lord Shiva with affection, for the sake of obtaining a good son.

Then Lord Vishnu appears as their son and the sons continue the tradition of worshipping clay idols of Lord Shiva.