The engagement was held in a Patna hotel on April 18 in the absence of Prasad.
Former Bihar Deputy Chief Minister, Tejaswi Yadav was seen sitting beside his elder brother during the ceremony.
Lalu is already out on three days parole to attend the marriage of his eldest son Tej Pratap on May 12 in Patna. "His parole has been granted for 3 days and the effective date of parole will be depended upon when jail authorities would release him", IG (Prisons) Harsh Mangla told PTI.
Not only a parole, Lalu Prasad Yadav also managed to get a bail for six weeks on medical grounds.
Since he landed in Patna on Friday, Prasad has remained mostly indoors, choosing to meet only select people inside his 10, Circular Road residence, while overseeing preparations for the wedding.More news: White House refuses comment about Sadler's McCain remark
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"We are glad that our leader has finally been allowed to attend wedding of his son".
Nitish Kumar, who has strained relations with the RJD chief's family ever since walked away from the Grand Alliance and returned to the BJP-led NDA, was greeted with loud cheers from the gathering.
JD (U) chief Nitish Kumar had previous year walked out of the grand alliance with RJD supremo Lalu Prasad Yadav. Jha alleged that Parasad was "forcibly sent back" to Ranchi from AIIMS "notwithstanding his fragile health which deserves best-possible medical care".
The wedding was solemnized at the sprawling Bihar Veterinary College ground in the presence of several party leaders and dignitaries. This is the first time that the two Bihar leaders have been seen together on a stage after Nitish Kumar chose to snap ties with RJD in Bihar.
"Heartiest congratulations @laluprasadrjd Lalu Ji on the happy occasion of the marriage of your son".