Stay Order

yes you can . you can approach local lawyer and consult with him and seek advice, act accordingly

If you have been enjoying such drinking water through pipeline through other's house you are having "Easement right" and you can contact a local advocate and can obtain a permanent injunction against the neighbor obstructing your easement rights, specific to drinking water.  As your brother is senior most citizen, your advocate can speed up the trial if any

Since property situates at Una ( H.P ) where your righted are infringing so as per sec 16 of CPC suit can be filed where immovable property situates so no any legal action can be initiated at Sonipat.You have to file injunction suit against your neighbour at Una H.P ) and get him restrained by stay order.

"not allowing him to cross-drinking water pipe thru the passage

 Is the Passage a common property between you and your neighbor?

Yes common passage is there

Well analysed, opined and advised by expert Mr. Bhartesh Goyal ji, I agree and appreciate.

Since the property vis-a-vis water connection is situated in Una, the jurisdictional court of Una shall decide the case/ dispute.

Therefore, it is better to consult and engage a local prudent lawyer in Una and not Sonepat, for appreciation of facts / documents, professional advise and necessary proceeding.

Instead of the jurisdictional Court of Law, the local SDO/RDO may also be approached in the given context.

You can engage th lawyer from Sonipat to file a suit for mandatory injunction at District court Una (HP). there is no bar for it.

However it would be expensive hence you may better engage an advocate in Una itself and file the law suit as suggested for the relief and remedy

The providing of free legal services /Aid through the District Legal Services Authority is only for the qualified litigants alone.  Do not depend on such services even if you are qualified as it is time-consuming and convincing them without influence is not easy.  Engage an advocate as getting an injunction is not a difficult task as a facility for drinking water can be examined and payment of taxes can also be confirmed.  I never heard that Govt provides local lawyers free of cost for civil matters like an injunction to all.   This is your family issue and this has to be sorted through your friends and relatives by availing professional services to avoid complications to your father.  Now that you have read entire posts, realize the urgency and it is time for action.  There can be no further guidance more than this, whatever you get is just a repetition of what was said in earlier posts.