Shiv Sena (UBT)'s Uddhav Thackeray and MNS' Raj Thackeray will join a protest on July 5 in Mumbai against the Maharashtra government's move to make Hindi compulsory as a third language in primary schools, Sanjay Raut said. This will reportedly mark the first time in two decades that the cousins unite over an issue. Earlier, both had announced separate demonstrations.