As ,by the time your wife reaches pensionable age, the authorities will probably demand many more years of PRSI contrIbutions than at present it is worth employing your wife so as to start building up those contributions.
I had the opposite problem. Stupidly, for many years, I never declared my wife as an employee ,even though she did indeed spend several hours doing the books for my business.
When I eventually did put her on the books we had an investigator come round the house to check whether she really was working. Took two hours of questions.
It wasn't the Revenue people -it was a "deciding officer, scope Section, Dept of Social and Family Affairs."
So, they do check sometimes that a spouse is a bona-fide employee ,even if working from home and even if for a few hours.