Property in wifes name

sir i have purchased a plot in my wifes name and built a house by my retired benfit money and bank loan and other savinngs and sale some ornament of my wife .we are 4 brothers i am youngest of them,now i have filed a partition suit on my fathers property now they also 3 brothers jointly filed a counter claim against my selfaquired property, which is in my wifes name, they saying 

that we have also paid money and labour to the said property (which is my wifes name) and that also our joint property .but they have no evidence for contribute any money.but i have spent 9 lakhs on that house .i have only the evidence of bank loan  and also our 3 sisters also signed and  make affidavit on court against that property(which is in my wifes name)so can they prove it its a joint hindu family property. or as treated as a streedhan property.