By V. Jagannathan

Chennai, April 5 (IANS) It is a family affair all right. But just how it ends will determine the future of the DMK, one of India's oldest political parties, and the political kaleidoscope of Tamil Nadu.

As DMK chief and Chief Minister M. Karunanidhi prepares to call it a day, an unlikely war has broken out in his family. It is a script the political veteran of over four decades is finding deeply embarrassing.

Elder son M.K. Alagiri is defying father Karunanidhi's carefully nurtured plans to annoint younger son M.K. Stalin as his heir.

Both Alagiri, 59, and Stalin, 57, are graduates in humanities. Both are cricket lovers. But while Alagiri lives in distant Madurai, Stalin resides in capital Chennai, whose high-profile mayor he has been.

After the DMK joined Prime Minister Manmohan Singh's government in May 2009, Alagiri became its chemicals and fertilizer minister on Karunanidhi's advice in a bid to clear the decks for Stalin in Chennai.

A day later, Stalin, a minister in Tamil Nadu, was elevated as the state's deputy chief minister.

The title left no one in doubt who would head the Tamil Nadu government and the DMK once Karunanidhi gave up control. In addition, Stalin was given many of the portfolios handled by Karunanidhi.

The arrangement seemed to be working fine until Alagiri told a Tamil magazine last month that he would not accept anyone else as his leader if and when his father hangs his boot.

The 86-year-old Karunanidhi, who had stated that he would retire in June after the World Classical Tamil Conference (WCTC) in Coimbatore, was taken aback.

Karunanidhi himself is one of India's most colourful politicians. He married thrice and two wives are alive. Stalin and Alagiri are sons from his second wife while the third wife's only daughter, Kanimozhi is a Rajya Sabha member.

DMK leaders believe Alagiri is perhaps testing the waters and that he might be happy being the DMK chief even if Stalin becomes chief minister.

But Stalin fears this would bring in a rival power centre.

Karunanidhi, who has been active in politics ever since the DMK first stormed to power in Tamil Nadu in 1967, has not taken kindly to Alagiri's anti-Stalin comments.

Alagiri, the DMK strongman from Madurai, found Delhi uncomfortable. He found it difficult to face even Question Hour in parliament because of his inability to speak in English and Hindi.

It was a matter of time before Alagiri, even while being a central cabinet minister, intruded into Tamil Nadu politics.

The DMK's South Zone Organisational Secretary and in charge of eight sprawling southern districts, Alagiri is said to have played a key role in its victory in all by-elections since it took office in 2006.

He was also instrumental in creating dissensions in rival AIADMK's camp by pinching some of its legislators.

But overseen by Karunanidhi, the DMK is not laudatory of Alagiri. To his discomfort, a DMK Working Committee resolution praised Stalin for handling political issues but kept mum about him.

To add insult to injury Karunanidhi ordered the removal of banners of the newly formed 'Alagiri Peravai', a group within the DMK supporting Alagiri, at the Working Committee meeting venue.

For now, Stalin is keeping himself away from the leadership row. "The party never gives any post to anyone violating any rule," he has said in remarks obviously directed at his brother.

A Stalin sympathiser told IANS: "Stalin was groomed by his father and he has come up in the party ladder. The DMK has seen him perform for several decades. This is not true for Alagiri."

DMK leaders rule out the chances of anyone upstaging Stalin.

But if Alagiri does that, the well-knit DMK could get split. It would then be advantage for non-DMK forces in Tamil Nadu, a possibility Karunanidhi dreads.