After end of Sri.Rama's coronation at Ayodya(after defeating   Ravana & bringing back Seetha)Sugreeva,Angadhan,Jambavan started to return  to their palaces.Hanuman stayed in Ayodya as he never wanted to be separated  from Sri.Rama.Now it was the turn of King Vibeeshana to leave from Ayodya.He was in tears as it was Sri Rama & Hanuman when he was driven out by his brother Ravana who  accepted him as he was from the enemy camp amid  objection  from  Vanara king Sugreeva.Even  before crossing the Sedhu Samudram & dethroning Ravana, Rama crowned Vibeeshna as the King of Lanka.He might  have thought  these things in his mind.Rama gave him their family Deity Lord Ranganadha to Vibeeshana & asked him to take it with him advising not to place it  on the earth until he reaches his palace at Lanka.Vibeeshana was returning to Lanka flying towards South direction to reach his destination.When he was over Srirangam,he wanted to go to bath room.&descended near the island formed by Rivers Cauvery & Coleroon (காவிரிக்கும் ,கொள்ளிடத்திற்கும்  நடுவில்  இருக்கும் ஸ்ரீ ரங்கம்).He saw a small boy standing there.He handed over the idol  to him asking him to keep it with him &requested  him not to place down as it is very Holy one.The boy agreed  but  with one condition that he would keep it & count numbers 1,2 & 3 at intervals before which Vibeeshan should get back from him.But it happened so that the boy counted the numbers & placed the  idol on the earth to the dissatisfaction of Vibeeshan .Vibeeshan tried to lift it but could not.So he chased the boy where as the boy ran towards a hill near by & climbed to the top of the hill.Meanwhile Lord Ranganadha told Vibeeshana that he likes the place very much & wants to stay there, however he assured him that he would look towards Lanka           ( southern direction)always.The boy who came there is none other than Lord Vinayaka.He stayed at that hill top & which is later called as Uchi Pillayar Koil(உச்சி  பிள்ளையார் கோயில்).Right below that a temple is carved  ( Pallava  cave temples) by ealier king.It is dedicated  to   Lord Siva.During olden days a young girl  got married & lived at Tiruchirappalli.She was the only child of an old lady who stayed away from Tiruchi. In due course ,the young married girl became pregnant & and her mother assured  her that she  would be by her side during the baby delivering time &that time also soon came.The matter was conveyed to  her mother.She was travelling towards Tiruchi from the other side of Cauvery.It  became  very dark & night time.There was a heavy flood in Cauvery.It could be crossed only by a boat,But the boat men refused to run the boat as it was very dark & heavy flood.The old woman was much worried that she could not  reach her daughter by that night itself & prayed to  Lord Siva to protect her  daughter&thought that she could reach the other side by tomorrow morning,To her relief,the flood got receded by the next day morning & reached her daughter's house.She saw her daughter with her new born baby & told her even though she  tried to reach her in time,she could not cross the river due to flood,But her daughter replied,what are you talking,you came here yesterday night  itself &you were with me &helped me in delivering the baby.Now that old lady realized that it was lord Siva himself  who came there in her  disguise &took care of her daughter.When her daughter & others came to know about that they were all in tears & began to praise Lord Siva & from that day on wards He is called Thayumanavan(தாயுமானவன்) the person who became a mother to protect a pregnant girl.That is why Manicka vasagar praises Him as the person better than  a mother who  feeds her child with her milk,