Answer the question about text:

I have already installed the spy cams in my office and my home because even my wife is working and we have to leave our little child with the nanny at home . We thought that after installing the spy cam at our home we can give our child the best protection . My sister in law was worried about the thefts which were happening in her shop .

Why does the narrator install the spy cams at home ?
They do n't completely trust the caretaker .