Urmila slept on behalf of Lakshmna

In some version of ramayan it might be there that Urmila was sleeping for 14 years. This as per the instruction of Lakshmana, he told to sleep on his behalf , as he'll not be able to sleep while serving Rama and Sita for 14 years. As the period of ramayana, husband and wife are suppposed to be one sole, one heart, one atma etc, one might serve the purpose other.

Lakshmana had (according to scriptures) had given his share of sleep to urmila, when he went to forest for 14 yrs. During rama's pattabhisheka after his forest life for the first time he yawns, so he finds it funny that the sleep that did not affect him for 14 yrs had overtaken him now as he felt sleepy so Lakshmana Laughed during Ram's Pattabishekam time

http://devdutt.com/articles/ramayana/lakshmans-wife-goes-to-sleep.html

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